Pith. sign in

REVIEW 2 major objections 5 minor 51 references

Doppler Pulse Amplification

T0 review · 2 major / 5 minor · reviewed 2026-08-07 · deepseek-v4-flash

Challenge this review Re-run · record.json Download PDF Read on arXiv ↗

Pith's one-line read Doppler pulse amplification can stretch, amplify, and recompress ultrashort pulses without chirping, and it avoids the gain narrowing that limits chirped pulse amplification.

desk verdict A genuinely new pulse-amplification architecture with sound Doppler math, but the gain-narrowing benefit rests on an unstated amplifier at a strongly downshifted frequency that the paper never shows exists. read the letter →

arxiv 2506.01447 v3 pith:4EJSQJJC submitted 2025-06-02 physics.optics

Klaas De Kinder , Amir Bahrami , Christophe Caloz This is my paper
classification physics.optics
keywords Dopplerpulseamplificationspace-timewedgesultrashortgainnarrowingchirpedFresnelprofilemovinginterfacestemporalcompansion
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

Doppler pulse amplification (DoPA) is proposed as an alternative to chirped pulse amplification (CPA) for boosting ultrashort pulses. Instead of dispersive gratings, it uses paired moving interfaces, called space-time wedges, that Doppler-shift the pulse: an opening wedge stretches the pulse while narrowing its spectrum, an amplifier boosts it, and a closing wedge recompresses it. Because the spectrum is already narrow when it reaches the amplifier, a much narrower gain band suffices, so gain narrowing is avoided. The paper also shows a space-time Fresnel version of the wedges that shrinks the device length by about two orders of magnitude for the example parameters. If it works, DoPA would offer a more compact and potentially higher-energy route to high-intensity ultrashort pulses.

What carries the argument

The central object is the paired space-time wedge: two perfect-electric-conductor interfaces moving at normalized velocity $\beta = v_m/c$, configured either opening (interfaces recede, so the pulse meets only comoving interfaces) or closing (interfaces approach, so it meets only contramoving interfaces). Each reflection applies the Doppler factor $R = (1 \mp \beta)/(1 \pm \beta)$ to the frequency and spectral width, and the Fourier relation makes the temporal width scale as $R^{-1}$; after $p$ reflections, $\omega_p = R^p \omega_0$ and $\tau_p = R^{-p} \tau_0$. This uniform spectral scaling is the mechanism: it stretches and compresses the pulse without adding chirp, and it is what lets the intermediate amplifier see a narrowed spectrum. The space-time Fresnel profile replaces the continuous wedge trajectory with a sawtooth reset after each bounce, which preserves the same compansion while shortening the device.

What would settle it

Send an ultrashort pulse through a single opening wedge and measure the frequency sweep across the stretched pulse: the paper predicts zero chirp, so any measured residual group-delay dispersion across the pulse would falsify the no-chirping mechanism.

Watch

Extended reading notes

Core claim

The paper claims that a pulse bounced $p$ times inside an opening space-time wedge emerges stretched by a factor $a = \tau_p/\tau_0 = R^{-p}$ with its center frequency and spectral width both scaled by $R^p$, where $R = (1-\beta)/(1+\beta) < 1$ for comoving interfaces. Since the entire spectrum scales uniformly, the pulse acquires no chirp. A closing wedge with contramoving interfaces applies $R^{-1}$ per bounce, exactly reversing the spectral and temporal changes, so the amplified pulse exits with its original duration and shape but higher peak power. The key consequence is that during the stretching stage the spectral width shrinks while the pulse lengthens, so the amplifier sees a narrow spectrum at a downshifted center frequency; after recompression the original broad spectrum is restored without the gain narrowing that CPA suffers. The paper derives device-length formulas for both the wedge geometry, $l_w = a(2/(1+\beta)+\beta)c\tau_0$, and the compact space-time Fresnel version, $l_f = 2(1+a\beta)c\tau_0$, and demonstrates the pulse dynamics with space-time diagrams and spectra.

Load-bearing premise

The whole approach depends on there being a gain medium whose amplification band is centered on the strongly downshifted, narrowed spectrum of the stretched pulse, and that medium must amplify without disturbing the moving interfaces; the paper assumes this amplifier exists but does not identify one.

Editorial extensions

If this is right

  • DoPA lets a much narrower-band amplifier be used for a given final pulse duration, because the spectrum is compressed during the stretching stage rather than kept constant as in CPA.
  • The output pulse recovers the input duration and shape without any dispersion compensation, since the Doppler compansion introduces no chirp.
  • For the example of a 10 fs pulse with compansion factor $10^6$ and $\beta = 0.01$, the space-time Fresnel implementation reduces device length from about 6 m to about 6 cm.
  • At fixed device length, the Fresnel implementation can add an extra expansion-compression pair, lowering the pre-amplification peak power further and permitting a higher gain before the amplifier saturation threshold is reached.
  • The wedge implementation has a minimum device length at $\beta = \sqrt{2}-1$, independent of the compansion factor and the initial pulse duration.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • The gain-narrowing benefit presupposes an amplifier that works at the Doppler-downshifted center frequency; if no such gain medium exists in a target spectral range, the scheme would need an additional wavelength-shifting stage, which the paper does not discuss.
  • Because DoPA introduces no chirp, it could in principle be combined with chirped pulse amplification or divided-pulse amplification in hybrid chains to relax bandwidth requirements; this is an extrapolation, not a claim in the paper.
  • The Fresnel sawtooth reset requires synchronization between the two moving boundaries; a natural next test is to quantify how timing jitter degrades the output pulse, since the paper only notes the requirement.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

2 major / 5 minor

Summary. The manuscript proposes Doppler pulse amplification (DoPA), in which an ultrashort pulse is stretched by repeated reflections from a moving opening space-time wedge (Doppler downshift and spectral narrowing), amplified, and then recompressed by a paired closing wedge (Doppler upshift and spectral broadening). The authors derive the Doppler scaling of center frequency and pulse width (Eqs. (1)-(2)), the device length for a wedge profile (Eq. (3)) and for a space-time Fresnel profile (Eq. (4)), and they present schematic demonstrations in Figs. 3-5. The central claim is that because the opening wedge narrows the spectrum before amplification, a narrow-band amplifier can be used without the gain narrowing that limits CPA.

Significance. If the intermediate-amplifier problem can be resolved, DoPA is a conceptually interesting addition to CPA and DPA, and the Fresnel implementation offers concrete compact-device scaling (Eq. (4)) with explicit experimental parameters. The geometric and Doppler derivations are internally consistent, the device-size formulas are explicitly derived in Appendix B, and the paper makes falsifiable predictions for device length as a function of compansion factor, modulation velocity, and input duration. The paper is also candid that generating moving interfaces is a major experimental challenge and connects to existing time-interface experiments. However, the headline advantage over CPA rests on an unsupported assumption about the availability of a gain medium at the Doppler-shifted intermediate frequency, and this must be addressed before the central claim can be accepted.

major comments (2)
  1. [Sec. II and Fig. 1b; Eq. (1)] The gain-narrowing argument compares the narrowed spectral width Δω'_in in DoPA with Δω_in in CPA, but it does not account for the fact that the center frequency is also Doppler-shifted. Equation (1) scales the entire spectrum, so both the center frequency and the spectral width are divided by a for an opening wedge with a>1. Claiming a benefit from the reduced width therefore presumes an amplifier whose passband is centered at ω0/a and whose absolute bandwidth is at least Δω_in/a. The paper never names or models such a gain medium. For the optical example in Sec. VI, a 10-fs near-infrared pulse (e.g., 800 nm) with a=10^3 would have its intermediate carrier at roughly 375 GHz and its narrowed bandwidth at roughly 44 GHz, a regime where no high-power femtosecond optical amplifier is identified; for a=10^6 the carrier is in the RF range. Without a concrete amplifier proposal, the central claim that DoPA mitigates gain narrowing is not established.
  2. [Secs. III-IV and Figs. 3-5] The amplifier is inserted between the opening and closing wedges, but no model or criterion is given for how the amplifier affects the stretched pulse. Recompression requires that the closing wedge's Doppler upshift exactly undo the opening wedge's downshift, so any frequency-dependent gain or phase from the amplifier will break this reversal. At a minimum, the authors should state the required amplifier transfer function (e.g., flat gain and linear phase across the narrowed bandwidth) and show that a realistic medium can provide it. As written, the amplification step is only an ideal multiplicative factor G, and the paper does not demonstrate that the final pulse retains its original shape and spectrum after a physical gain stage.
minor comments (5)
  1. [Sec. VI] The optical example does not specify the input center wavelength or spectral width, so the intermediate frequency and narrowed bandwidth cannot be checked from the given parameters; these values should be stated explicitly.
  2. [Eqs. (1)-(2) and Sec. VI] The example β=1/√3 and a=10^3 implies p = log_R(1/a) ≈ 5.24, but p denotes the number of scattering events and must be an integer; the example should instead state an integer p and the resulting value of a.
  3. [Sec. II] The phrase "dynamically alternating the pulse spectrum" in the fourth paragraph appears to mean "dynamically shifting the pulse spectrum"; please correct the wording.
  4. [Fig. 1 caption] The amplifier passband G_DoPA is drawn in Fig. 1b, but its center frequency and bandwidth are not defined in the text; this should be made explicit and consistent with the Doppler-downshifted carrier.
  5. [Sec. VI] There is a minor typo in "pump-probe setu ps" in the paragraph on optical experiments; it should be "pump-probe setups."

Circularity Check

0 steps flagged · score 0.0 of 10

DoPA derivation is internally consistent; the gain-narrowing caveat is a missing amplifier feasibility argument, not circularity.

full rationale

The paper's claimed derivation chain—Doppler downshifting per reflection (Eq. (1)/(A6)), temporal stretching via the Fourier relation (Eq. (2)/(A7)), spectral narrowing by the same uniform scaling factor, recompression by a matched closing wedge, and the device-length formulas (Eqs. (3), (4), (B10), (B14))—is internally self-contained and is not equivalent to its inputs by construction. The central input is the space-time wedge scattering solution from the authors' prior work [36], which is a published external result with independent content about wedges themselves, not a restatement of pulse amplification or gain-narrowing mitigation. The gain-narrowing mitigation claim follows directly from the uniform spectral scaling R^p applied to both center frequency and bandwidth; it is a physical consequence, not a fitted parameter renamed as a prediction. The largest caveat is practical, not circular: the intermediate amplifier centered at the Doppler-downshifted frequency is assumed to exist (Fig. 1b, Sec. II) and is never identified (Sec. VI discusses only interface generation, not the amplifier). That is a missing feasibility argument, not a self-referential derivation. Self-citations [36]–[38] are load-bearing for the scattering solution and the 'no chirping' assertion, but they are not invoked to forbid alternatives or to define the target result, and they are not equivalent to the paper's own conclusion. Therefore, under the stated criteria, no significant circularity is present.

Assumptions & free parameters 2 free parameters · 6 assumptions · 0 invented entities

The central claims rest on the moving-interface scattering model from the authors' own prior work, plus ideal PEC, Fourier-limited, no-dispersion assumptions. The most consequential unstated assumption is availability of a gain medium at the downshifted frequency.

free parameters (2)
  • beta (normalized modulation velocity) = examples: 0.01, 0.17, 1/sqrt(3)
    Design parameter governing Doppler shift per bounce and device length; chosen by hand in the examples (Sec. III, Sec. VI), not derived or fitted to data.
  • a (compansion factor) = examples: 1e2, 1e3, 1e6
    Required stretch/compress ratio; chosen by hand (Sec. IV, V). Determines the number of bounces p = ln(a)/ln(1/R) and therefore the device size.
assumptions (6)
  • domain assumption Moving PEC interfaces are ideal perfect conductors with no losses and constant velocity beta throughout the interaction.
    Invoked in Sec. III and Appendix A; the scattering solution Eq. (A1) is built on PEC boundary conditions. Real interfaces would have losses and velocity dynamics.
  • domain assumption Each reflection applies the same Doppler factor R = (1 -/+ beta)/(1 +/- beta) to the whole spectrum; no dispersion, chirp, or mode conversion.
    Used in Eq. (1) and Eq. (2); the paper cites uniformity of the space-time structure [37,38].
  • domain assumption The pulse obeys the Fourier limit, so temporal width scales as the inverse of spectral width (tau_p/tau_0 = R^-p).
    Stated in Appendix A3 as 'Due to the Fourier limit'; assumes transform-limited pulses and no chirp.
  • standard math The scattering solution of the space-time wedge in ref. [36] is correct and applies here.
    Appendix A1 says Eq. (A1) is a particular case of Eq. (5) of [36].
  • domain assumption The space-time Fresnel profile can reset (sawtooth) the interface positions without producing spurious reflections that corrupt the pulse.
    Invoked in Sec. V and Appendix B2; the paper notes synchronization is critical but does not model the reset process.
  • domain assumption A gain medium with its gain band centered at the Doppler-downshifted intermediate frequency exists and can amplify the stretched pulse.
    Implicit in the gain-narrowing mitigation claim (Fig. 1b and Sec. II); never stated or justified.

how reviews work

0 comments
Cite this review

Pith. "Pith review of Doppler Pulse Amplification." pith.science (2026). https://pith.science/paper/4EJSQJJC

@misc{pith2026250601447,
  author       = {Pith},
  title        = {Pith review of: Doppler Pulse Amplification},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/4EJSQJJC}},
  note         = {Machine review of arXiv:2506.01447}
}
read the original abstract

The ability to amplify ultrashort pulses has revolutionized modern laser science, driving advances in various fields such as ultrafast optics and spectroscopy. A pivotal development in this field is chirped pulse amplification (CPA), which stretches, amplifies and recompresses ultrashort optical pulses using dispersive elements to overcome amplification limits. However, CPA faces limitations due to gain narrowing, restricting the final pulse duration. Here, we propose Doppler pulse amplification (DoPA), a novel approach for amplifying ultrashort pulses. While DoPA shares similarities with CPA in that it also stretches, amplifies and recompresses pulses, it differs in how it achieves this temporal compansion. Unlike CPA, DoPA exploits Doppler shifts induced by space-time modulated interfaces through a space-time wedge implementation without chirping. We show that DoPA dynamically shifts the pulse spectrum, effectively mitigating the gain narrowing issue of CPA. Additionally, we show that DoPA enables more compact amplification systems via a space-time Fresnel implementation. This approach may pave the way for more efficient, high-intensity laser systems and expand the potential for applications in both laboratory research and practical environments.

Figures

Figures reproduced from arXiv: 2506.01447 by the authors.

Figure 1
Figure 1. FIG. 1. General concept of (a) chirped pulse amplification (CPA) and (b) proposed Doppler pulse amplification (DoPA). In [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 2
Figure 2. FIG. 2. Implementation of the space-time wedges in the [PITH_FULL_IMAGE:figures/full_fig_p003_2.png] view at source ↗
Figure 3
Figure 3. FIG. 3. Demonstration of the DoPA system in Fig. 1b with [PITH_FULL_IMAGE:figures/full_fig_p004_3.png] view at source ↗
Figures from the paper (2 more)
Figure 4
Figure 4. Figure 4: FIG. 4. Realization of DoPA (Fig. 1b) using a space-time [PITH_FULL_IMAGE:figures/full_fig_p005_4.png]
Figure 5
Figure 5. Figure 5: FIG. 5. DoPA using a space-time Fresnel structure with the [PITH_FULL_IMAGE:figures/full_fig_p005_5.png]

Discussion (0). Sign in to comment.

Reference graph

Works this paper leans on

51 extracted references · 49 canonical work pages

  1. [36]

    Guichard, M

    F. Guichard, M. Hanna, Y. Zaouter, D. N. Papadopou- los, F. Druon, and P. Georges, Analysis of limitations in divided-pulse nonlinear compression and amplification, IEEE J. Sel. Top. Quantum Electron 20, 619 (2014)

    work page 2014

  2. [1]

    (5) of [36], with v1 = ∓βc, v2 = ±βc and u = c, where the top sign refers to an opening space-time wedge and the bottom sign to a closing wedge

    Scattering Solution The scattering solution, Ew, for an electromagnetic wave inside a space-time perfect electric conductor wedge with both interfaces moving at a constant normalized ve- locity β is a particular case of the expressions in Eq. (5) of [36], with v1 = ∓βc, v2 = ±βc and u = c, where the top sign refers to an opening space-time wedge and the b...

    work page

  3. [2]

    (A1): ωp = ∂Φp ∂t ω0 = Rpω0

    Doppler Shift The shifted frequency, ωp, after p bounces may be cal- culated by taking a time derivative of the phase argument in Eq. (A1): ωp = ∂Φp ∂t ω0 = Rpω0 . (A6)

    work page

  4. [3]

    (A6)], the temporal envelope of the pulse also undergoes modifi- cation

    Compansion F actor In addition to the frequency Doppler shift [Eq. (A6)], the temporal envelope of the pulse also undergoes modifi- cation. Due to the Fourier limit, the width of the optical pulse changes by a factor R−p. Thus, the compansion factor, a = τp/τ0, defined as the ratio of the width of the reflected wave, τp, and the width of the incident wave...

    work page

  5. [4]

    2) required for the compansion fac- tor [Eq

    W edge Profile In this section, we determine the minimal size of the wedge profile (Fig. 2) required for the compansion fac- tor [Eq. (2)] to equal a after p bounces. We perform 7 the analysis for the pulse expansion (first step in DoPA, Fig. 1), i.e., an opening space-time wedge (Fig. 2a). The two edges of the space-time wedge may be parametrized as zL[t...

    work page

  6. [5]

    The characteristic wavelength of this profile, λf, is given by λf = βcT

    F resnel Profile The space-time Fresnel trajectory can be parametrized as a sawtooth profile with period T and constant velocity β. The characteristic wavelength of this profile, λf, is given by λf = βcT . (B11) The total device length, lf, consists of two contributions: (i) twice the distance traveled by the interface in a single oscillation [Eq. (B11)] ...

    work page

  7. [6]

    Bromage, Raman amplification for fiber communica- tions systems, J

    J. Bromage, Raman amplification for fiber communica- tions systems, J. Lightw. Technol. 22, 79 (2004)

    work page 2004

  8. [7]

    Keiser, Optical Fiber Communications , 2nd ed

    G. Keiser, Optical Fiber Communications , 2nd ed. (McGraw-Hill New York, 2000)

    work page 2000

Show all 51 references
  1. [8]

    C. E. Cook, Pulse compression—Key to more efficient radar transmission, Proc. IRE 48, 310 (1960)

    1960

  2. [9]

    Meikle, Modern Radar Systems , 2nd ed

    H. Meikle, Modern Radar Systems , 2nd ed. (Artech House, 2008)

    2008

  3. [10]

    Krishnanm and M

    S. Krishnanm and M. Mudrich, Intense laser matter in- teraction in atoms, finite systems and condensed media: Recent experiments and theoretical advances, Eur. Phys. J. Spec. Top. 230, 3981 (2021)

    2021

  4. [11]

    S. Niu, W. Wang, P. Liu, Y. Zhang, X. Zhao, J. Li, M. Xiao, Y. Wang, J. Li, and X. Shao, Recent advances in applications of ultrafast lasers, Photonics 11, 857 (2024)

    2024

  5. [12]

    Malka, S

    V. Malka, S. Fritzler, E. Lefebvre, M.-M. Aleonard, F. Burgy, J.-P. Chambaret, J.-F. Chemin, K. Krushel- nick, G. Malka, S. P. D. Mangles, Z. Najmudin, M. Pittman, J.-P. Rousseau, J.-N. Scheurer, B. Walton, and A. E. Dangor, Electron acceleration by a wake field forced by an i...

    2002

  6. [13]

    Faure, C

    J. Faure, C. Rechatin, A. Norlin, A. Lifschitz, Y. Glinec, and V. Malka, Controlled injection and acceleration of electrons in plasma wakefields by colliding laser pulses, Nature 444, 737 (2006)

    2006

  7. [14]

    B. E. A. Saleh and M. C. Teich, Fundamentals of Pho- tonics, 3rd ed. (New York: Wiley, 2019)

    2019

  8. [15]

    Juhasz, G

    T. Juhasz, G. A. Kastis, C. Su´ arez, Z. Bor, and W. E. Bron, Time-resolved observations of shock waves and cav- itation bubbles generated by femtosecond laser pulses in corneal tissue and water, Lasers Surg Med. 19, 23 (1996)

    1996

  9. [16]

    M. E. Fermann and I. Hartl, Ultrafast fibre lasers, Nat. Photonics. 7, 868 (2013)

    2013

  10. [17]

    Yablonovitch, Self-phase modulation of light in a laser- breakdown plasma, Phys

    E. Yablonovitch, Self-phase modulation of light in a laser- breakdown plasma, Phys. Rev. Lett. 32, 1101 (1974)

    1974

  11. [18]

    M. D. Perry, T. Ditmire, and B. C. Stuart, Self-phase modulation in chirped-pulse amplification, Opt. Lett. 19, 2149 (1994)

    1994

  12. [19]

    Strickland and G

    D. Strickland and G. Mourou, Compression of amplified chirped optical pulses, Opt. Commun. 56, 219 (1985)

    1985

  13. [20]

    Strickland, Nobel lecture: Generating high-intensity ultrashort optical pulses, Rev

    D. Strickland, Nobel lecture: Generating high-intensity ultrashort optical pulses, Rev. Mod. Phys. 91, 030502 (2019)

    2019

  14. [21]

    Maine, D

    P. Maine, D. Strickland, P. Bado, M. Pessot, and G. Mourou, Generation of ultrahigh peak power pulses by chirped pulse amplification, IEEE J. Quantum Elec- tron 24, 398 (1988)

    1988

  15. [22]

    Dubietis, G

    A. Dubietis, G. Jonuˇ sauskas, and A. Piskarskas, Powerful femtosecond pulse generation by chirped and stretched pulse parametric amplification in BBO crystal, Opt. Commun. 88, 437 (1992)

    1992

  16. [23]

    Z. Li, Y. Leng, and R. Li, Further development of the short-pulse petawatt laser: Trends, technologies, and bottlenecks, Laser Photonics Rev. 17, 2100705 (2023)

    2023

  17. [24]

    S. Zhou, F. W. Wise, and D. G. Ouzounov, Divided- pulse amplification of ultrashort pulses, Opt. Lett. 32, 871 (2007)

    2007

  18. [25]

    Kienel, A

    M. Kienel, A. Klenke, T. Eidam, S. H¨ adrich, J. Limpert, and A. T¨ unnermann, Energy scaling of femtosecond am- plifiers using actively controlled divided-pulse amplifica- tion, Opt. Lett. 39, 1049 (2014)

    2014

  19. [26]

    B. Webb, A. Azim, N. Bodnar, M. Chini, L. Shah, and M. Richardson, Divided-pulse amplification to the joule level, Opt. Lett. 41, 3106 (2016)

    2016

  20. [27]

    Stark, M

    H. Stark, M. M¨ uller, M. Kienel, A. Klenke, J. Limpert, and A. T¨ unnermann, Electro-optically controlled divided-pulse amplification, Opt. Express 25, 13494 (2017)

    2017

  21. [28]

    Stark, J

    H. Stark, J. Buldt, M. M¨ uller, A. Klenke, A. T¨ unnermann, and J. Limpert, 23 mJ high-power fiber CPA system using electro-optically controlled divided-pulse amplification, Opt. Lett. 44, 5529 (2019)

    2019

  22. [29]

    Zaouter, F

    Y. Zaouter, F. Guichard, L. Daniault, M. Hanna, F. Morin, C. H¨ onninger, E. Mottay, F. Druon, and P. Georges, Femtosecond fiber chirped- and divided-pulse amplification system, Opt. Lett. 38, 106 (2013)

    2013

  23. [30]

    L. J. Kong, L. M. Zhao, S. Lefrancois, D. G. Ouzounov, C. X. Yang, and F. W. Wise, Generation of megawatt peak power picosecond pulses from a divided-pulse fiber amplifier, Opt. Lett. 37, 253 (2012)

    2012

  24. [31]

    J. S. Coe, P. Maine, and P. Bado, Regenerative amplifi- cation of picosecond pulses in Nd:YLF: Gain narrowing and gain saturation, J. Opt. Soc. Am. B 5, 2560 (1988)

    1988

  25. [32]

    Backus, C

    S. Backus, C. G. Durfee III, M. M. Murnane, and H. C. Kapteyn, High power ultrafast lasers, Rev. Sci. Instrum, 69, 1207 (1998)

    1998

  26. [33]

    For a fixed amount of group velocity dispersion and a fixed stretching factor, the size of the diffraction grating scales with the square of the input pulse duration [9]— for instance, increasing the pulse duration from 10 fs to 10 ps requires enlarging the grating length by a...

  27. [34]

    Kienel, A

    M. Kienel, A. Klenke, T. Eidam, M. Baumgartl, C. Jau- regui, J. Limpert, and A. T¨ unnermann, Analysis of pas- sively combined divided-pulse amplification as an energy- scaling concept, Opt. Express 21, 29031 (2013)

    2013

  28. [35]

    Hanna, F

    M. Hanna, F. Guichard, Y. Zaouter, D. N. Papadopou- los, F. Druon, and P. Georges, Coherent combination of ultrafast fiber amplifiers, J. Phys. B 49, 062004 (2016)

    2016

  29. [37]

    Doppler, ¨Uber das farbige Licht der Doppelsterne und einiger anderer Gestirne des Himmels, K¨ onigl

    C. Doppler, ¨Uber das farbige Licht der Doppelsterne und einiger anderer Gestirne des Himmels, K¨ onigl. B¨ ohm Gedsellsch. d. Wis. 2, 465 (1842)

  30. [38]

    M. A. Gaafar, T. Baba, M. Eich, and A. Petrov, Front- induced transitions, Nat. Photonics. 13, 737 (2019)

    2019

  31. [39]

    Caloz and Z.-L

    C. Caloz and Z.-L. Deck-L´ eger, Spacetime metamaterials—Part II: Theory and applications, IEEE Trans. Antennas Propag. 68, 1583 (2019)

    2019

  32. [40]

    Deck-L´ eger, N

    Z.-L. Deck-L´ eger, N. Chamanara, M. Skorobogatiy, M. G. Silveirinha, and C. Caloz, Uniform-velocity space- time crystals, Adv. Photonics 1, 56002 (2019)

    2019

  33. [41]

    Bahrami, K

    A. Bahrami, K. De Kinder, Z. Li, and C. Caloz, Space- time wedges, Nanophotonics (2025)

    2025

  34. [42]

    Bahrami, Z.-L

    A. Bahrami, Z.-L. Deck-L´ eger, Z. Li, and C. Caloz, A generalized FDTD scheme for moving electromag- netic structures with arbitrary space-time configurations, IEEE Trans. Antennas Propag. 72, 1721 (2024). 9

    2024

  35. [43]

    De Kinder, A

    K. De Kinder, A. Bahrami, and C. Caloz, Scat- tering and chirping at accelerated interfaces (2025), arXiv:2506.19575

    2025

  36. [44]

    I. V. Yakovlev, Stretchers and compressors for ultra-high power laser systems, Quantum Electron. 44, 393 (2014)

    2014

  37. [45]

    Z. Li, X. Ma, A. Bahrami, Z.-L. Deck-L´ eger, and C. Caloz, Space-time Fresnel prism, Phys. Rev. Appl. 20, 054029 (2023)

    2023

  38. [46]

    Moussa, G

    H. Moussa, G. Xu, S. Yin, E. Galiffi, Y. Ra’di, and A. Al` u, Observation of temporal reflection and broad- band frequency translation at photonic time interfaces, Nat. Phys. 19, 863 (2023)

    2023

  39. [47]

    Galiffi, G

    E. Galiffi, G. Xu, S. Yin, H. Moussa, Y. Ra’di, and A. Al` u, Broadband coherent wave control through pho- tonic collisions at time interfaces, Nat. Phys. 19, 1703 (2023)

    2023

  40. [48]

    T. R. Jones, A. V. Kildishev, M. Segev, and D. Per- oulis, Time-reflection of microwaves by a fast optically- controlled time-boundary, Nat. Commun. 15, 6786 (2024)

    2024

  41. [49]

    Y. Zhou, M. Z. Alam, M. Karimi, J. Upham, O. Reshef, C. Liu, A. E. Willner, and R. W. Boyd, Broadband fre- quency translation through time refraction in an epsilon- near-zero material, Nat. Commun. 11, 2180 (2020)

    2020

  42. [50]

    Lustig, O

    E. Lustig, O. Segal, S. Saha, E. Bordo, S. N. Chowdhury, Y. Sharabi, A. Fleischer, A. Boltasseva, O. Cohen, V. M. Shalaev, and M. Segev, Time-refraction optics with single cycle modulation, Nanophotonics 12, 2221 (2023)

    2023

  43. [51]

    A. Ball, R. Secondo, D. Fomra, J. Wu, S. Saha, A. Agrawal, H. Lezec, and N. Kinsey, A space-time knife- edge in epsilon-near-zero films for ultrafast pulse charac- terization, Laser Photonics Rev. 19, 2401462 (2025)

    2025

Pith tools

Reviewed August 7, 2026 · model on record in the stance chip above.