Figure 1

Experimental setup. The green circle represents the ring resonator. “C” corresponds to the coupler.Reuse & Permissions

Figure 2

Experimental observations of the transmitted temporal pulse profiles in the fast-light system. (a) The upper right inset shows the transmission spectrum as a function of detuning frequency. In the main panel, the black and blue lines denoted by “i” and “ii” represent the input and output pulses, respectively. The input pulses were original Gaussian-shaped pulses. The pulse heights were normalized with respect to each other to show the peak advancement clearly. In (b) and (c), the input pulses were Gaussian-shaped pulses encoded with bending nonanalytical points on the leading and trailing edges, respectively. The black and blue lines denoted by “i” and “ii” represent the input and output pulses, respectively. The pulse heights were normalized by that of the input pulses. The vertical solid black line represents the peak time of the input pulses ($t$ $=$ 0) and the vertical dashed blue line represents the peak time of the output pulses. The dotted red lines in (b) and (c) represent the time when the bending nonanalytical points appeared.Reuse & Permissions

Figure 3

Similar plots as Fig. 2 for the slow-light system. (a) Original Gaussian-shaped pulses. (b) and (c) Gaussian-shaped pulses encoded with bending nonanalytical points on the leading and trailing edges, respectively. The notations “i” and “ii” and the vertical lines have the same meaning as those in Fig. 2.Reuse & Permissions

Figure 4

Distinction between traditional discontinuous and bending nonanalytical points in Fourier space. Left column: three types of input temporal profiles, $E\left(t\right)$: (a) original Gaussian-shaped pulses, and (b) and (c) Gaussian-shaped pulses encoded with the bending and discontinuous nonanalytical points, respectively. Middle column: (a′)–(c′) are the amplitudes of the Fourier components for the input pulses shown in (a)–(c), respectively. Right column: (a${}^{″}$)–(c${}^{″}$) are the amplitudes of the Fourier components for the first-order derivative of the input pulses shown in (a)–(c), respectively. The green-shaded region in (c′) and red-shaded regions in (b${}^{″}$) and (c${}^{″}$) are denoted to call attention to the wing Fourier components used to distinguish between the two types of nonanalytical points. The units for time and frequency are ($t_e$) and ($t_e^{-1}$), respectively.Reuse & Permissions

Figure 5

Effect of the finite spectral bandwidth of the incident pulses with respect to the bending point, in the slow-light system. (a) Original bending point. The black and blue lines denoted by “i” and “ii” represent the input and output pulses, respectively. (b) and (c) Bandwidth of the input pulse is restricted to $\Delta {\nu }_B\le t_e^{-1}$ and $\Delta {\nu }_B\le 0.5t_e^{-1}$, respectively. The black and green lines denoted by “i” and “ii” represent the bandwidth-restricted input and output pulses, respectively. The pulse heights were normalized by that of the original input pulse [panel (a) “i”]. The vertical solid black line represents the peak time of the input pulses ($t$ $=$ 0) and the vertical dashed blue line represents the peak time of the output pulses. The dotted red line represents the time when the bending points enter. The unit for time is $\left(t_e\right)$.Reuse & Permissions