Qian Li, K. Senthilnathan, K. Nakkeeran, and P. K. A. Wai, "Nearly chirp- and pedestal-free pulse compression in nonlinear fiber Bragg gratings," J. Opt. Soc. Am. B 26, 432-443 (2009)

We demonstrate almost chirp- and pedestal-free optical pulse compression in a nonlinear fiber Bragg grating with exponentially decreasing dispersion. The exponential dispersion profile can be well-approximated by a few gratings with different constant dispersions. The required number of sections is proportional to the compression ratio, but inversely proportional to the initial chirp value. We propose a compact pulse compression scheme, which consists of a linear and nonlinear grating, to effectively compress both hyperbolic secant and Gaussian shaped pulses. Nearly transform-limited pulses with a negligibly small pedestal can be achieved.

David Krčmařík, Radan Slavík, Yongwoo Park, and José Azaña Opt. Express 17(9) 7074-7087 (2009)

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

$C(0)$ is the normalized chirp coefficient of the chirped hyperbolic secant or Gaussian input pulse. The normalized chirp coefficients after the linear FBG $[C(0)]$ are determind by fitting the phase of the pulse using $C(0){t}^{2}\u2215{T}^{2}({L}_{\mathrm{LFBG}})\u22152$, where $T({L}_{\mathrm{LFBG}})$ is the pulse width parameter of the hyperbolic secant or Gaussian pulse. Similarly, the chirp coefficient of the compressed pulse, $C(z)$, is determined by fitting the phase of the pulse using $C(z){t}^{2}\u2215{T}^{2}({L}_{\mathrm{NFBG}})\u22152$, where $T({L}_{\mathrm{NFBG}})$ is the pulse width parameter of the compressed pulse.

Table 4

Comparison of the Pedestal Generated for Different Values of the $\text{Ratio}={L}_{D0,\mathrm{Gauss}}\u2215{L}_{N0,\mathrm{Gauss}}$^{
a
}

Ratio

Change of ${\beta}_{20}$

Change of Peak Power

1

6.49%

6.49%

1.2

1.47%

1.47%

$\sqrt{2}$

0.0935%

1.6

1%

1%

1.8

2.42%

2.38%

2

3.69%

3.68%

${L}_{D0,\mathrm{Gauss}}={T}_{\mathrm{Gauss}}^{2}({L}_{\mathrm{LFBG}})\u2215\mid {\beta}_{20}\mid $ and ${L}_{N0,\mathrm{Gauss}}=1\u2215{\gamma}_{g}\u2215{P}_{0}$ are the initial dispersion and nonlinear lengths, respectively, of the ratio. The different values of ${L}_{D0,\mathrm{Gauss}}\u2215{L}_{N0,\mathrm{Gauss}}$ are obtained by either changing the initial dispersion value of NFBG ${\beta}_{20}$ or changing the peak power of the initial pulse. Different lengths of NFBG are used to achieve the same FWHM of the final compressed pulse.

Tables (4)

Table 1

Comparison Between Different Pulse Compression Schemes

Large Compression Ratio

Pedestal-Free

Chirp-Free– Almost Chirp-Free

Avoid Wave Breaking at High Powers

Short Length

Higher-order soliton compression

√

Adiabatic pulse compression in fibers

√

Adiabatic pulse compression in NFBG

√

√

Self-similar pulse compression in fibers

√

√

√

√

Self-similar pulse compression in NFBG

√

√

√

√

√

Table 2

Values of the Constants ${c}_{i}$ in Eq. (12) for Different Choices of the Reduction Methods and Ansatz

$C(0)$ is the normalized chirp coefficient of the chirped hyperbolic secant or Gaussian input pulse. The normalized chirp coefficients after the linear FBG $[C(0)]$ are determind by fitting the phase of the pulse using $C(0){t}^{2}\u2215{T}^{2}({L}_{\mathrm{LFBG}})\u22152$, where $T({L}_{\mathrm{LFBG}})$ is the pulse width parameter of the hyperbolic secant or Gaussian pulse. Similarly, the chirp coefficient of the compressed pulse, $C(z)$, is determined by fitting the phase of the pulse using $C(z){t}^{2}\u2215{T}^{2}({L}_{\mathrm{NFBG}})\u22152$, where $T({L}_{\mathrm{NFBG}})$ is the pulse width parameter of the compressed pulse.

Table 4

Comparison of the Pedestal Generated for Different Values of the $\text{Ratio}={L}_{D0,\mathrm{Gauss}}\u2215{L}_{N0,\mathrm{Gauss}}$^{
a
}

Ratio

Change of ${\beta}_{20}$

Change of Peak Power

1

6.49%

6.49%

1.2

1.47%

1.47%

$\sqrt{2}$

0.0935%

1.6

1%

1%

1.8

2.42%

2.38%

2

3.69%

3.68%

${L}_{D0,\mathrm{Gauss}}={T}_{\mathrm{Gauss}}^{2}({L}_{\mathrm{LFBG}})\u2215\mid {\beta}_{20}\mid $ and ${L}_{N0,\mathrm{Gauss}}=1\u2215{\gamma}_{g}\u2215{P}_{0}$ are the initial dispersion and nonlinear lengths, respectively, of the ratio. The different values of ${L}_{D0,\mathrm{Gauss}}\u2215{L}_{N0,\mathrm{Gauss}}$ are obtained by either changing the initial dispersion value of NFBG ${\beta}_{20}$ or changing the peak power of the initial pulse. Different lengths of NFBG are used to achieve the same FWHM of the final compressed pulse.