Beyond-Bandwidth Electrical Pulse Modulation of a TO-Can Packaged VCSEL for 10 Gbit/s Injection-Locked NRZ-to-RZ Transmission

Abstract

Abstract-The parametric characterization of a nonreturnto-zero (NRZ) to return-to-zero (RZ) data format converter based on the external optical NRZ injection of a TO-46-can packaged vertical-cavity surface-emitting laser (VCSEL) directly modulated by a 10 GHz electrical pulse is demonstrated. The electrical-pulse modulation induced gain switching of the VCSEL is initiated under external optical NRZ data injection that increases the relaxation oscillation frequency of the homemade VCSEL from 2.2 to 7.4 GHz, thereby enabling its electrical modulation bandwidth up to 10 GHz. The external NRZ injection reduces the lasing threshold and enlarges the modulation depth of the VCSEL so that the converted RZ data pulsewidth can be shortened to 27 ps with a slightly increased peak-to-peak negative frequency chirp of 4.3 GHz (corresponding to a chirp parameter of 122 MHz/ps). The chirp and bit error rate (BER) display strong correlations with the injection power and the biased current of the VCSEL. With external injection, the receiving power required for achieving a BER below 10 9 at 10 Gbit/s is 19 5 dBm, and a power penalty of 16 dB is observed when the dc bias of the electrical-pulse modulated VCSEL is decreased by only 10% from the threshold condition.Index Terms-Chirp parameter, data format convertor, injection-locked, return-to-zero (RZ), vertical-cavity surface-emitting laser (VCSEL).

A pulsated weak-resonant-cavity laser diode with transient wavelength scanning and tracking for injection-locked RZ transmission

“…External injection compensates the loss of the resonant cavity, facilitating the lasing of the WRC-FPLD to build up at lower driving currents. The threshold current reduction can be theoretically derived as [13,14] 2 0…”

“…where q denotes the electronic charge, V the volume of the active region, τ c the carrier lifetime in active region, κ the coupling coefficient, g the stimulated emission rate, α the linewidth enhancement factor, S inj the photon number injected into the WRC-FPLD cavity, and S 0 the steady-state photon number [12][13][14]. The power-current slope remains almost constant at injection powers ranging between −12 and + 3 dBm.…”

“…The below-threshold modulation not only releases the temperature and the wavelength control of the slave WRC-FPLD, but also leads to the all-optical NRZ-to-RZ conversion under the optical carrier injection from the pulsed master source. Under the injection-locking condition, the stationary solution of the injection-locked slave WRC-FPLD must be re-derived using tracking rate equations [13,15],…”

40 Gbit/s Pulsed RZ-BPSK Transmission With a 40 GHz Self-Pulsated Distributed Feedback Laser Diode Mach–Zehnder Intensity Modulator Link

“…Alternatively, the all-optical NRZ-to-RZ data format conversion up to 10 Gbit∕s was proposed with directly modulated and injection-locked lasers or amplifiers [14][15][16][17]. With the use of semiconductor optical amplifiers [18][19][20], Mach-Zehnder interferometers [21][22][23], ring waveguides and resonators [24,25], and nonlinearly birefringent fibers [26][27][28][29][30], different kinds of OOK-to-PSK and NRZ-to-RZ format convertors were proposed and comprehensively investigated in past decades.…”

Phase synchronization scheme for a practical phase sensitive amplifier of ASK-NRZ signals

“…OPLLs suffer from a strict trade-off between laser linewidth and loop bandwidth, which prohibits low phase error operation with commercial off-the-shelf components [14,17]. On the other hand, OIL has been identified as a stable and reliable locking mechanism for laser synchronization [17], addressing a broad spectrum of applications that range from analog coherent detection [19][20][21] and direct modulation [22,23] to phase sensitive amplification [8,9] and all-optical digital storage [24,25]. However, although the physical properties of optical injection locking have been well investigated, the limitations that it imposes on the actual performance of black box PSAs have not been yet fully explored.…”