TY - JOUR
T1 - Theory and design of a tapered line distributed photodetector
AU - Shi, Jin Wei
AU - Sun, Chi Kuang
N1 - Funding Information:
Manuscript received January 16, 2002; revised July 11, 2002. This work was supported by the National Science Council of Taiwan under Grant NSC 89-2215-E-002-064 and the National Science Foundation of USA under Award INT-9813411.
PY - 2002/11
Y1 - 2002/11
N2 - We present the theory and design of a tapered line distributed photodetector (TLDP). In the previously demonstrated velocity-matched distributed photodetector (VMDP), high electrical bandwidth is achieved by proper termination in the input end to absorb reverse traveling waves, sacrificing one-half of the quantum efficiency. By utilizing the tapered line structure and phase matching between optical waves and microwaves in our analyzed structure, a traveling-wave photodetector is more realizable and ultrahigh bandwidth can be attained due to removal of the extra input dummy load that sacrifices one-half of the total quantum efficiency. To investigate the advantages of TLDP over VMDP, we calculate their electrical bandwidth performances by using an analytic photodistributed current model. We adopted low-temperature-grown (LTG) GaAs-based metal-semiconductor-metal (MSM) traveling-wave photodetectors as example unit active devices in the analytic bandwidth calculation for their high-speed and high-power performances. Both VMDP and TLDP in our simulation are assumed to be transferred onto glass substrates, which would achieve high microwave velocity/impedance and make radiation loss negligible. The simulated bandwidth of a properly designed LTG GaAs MSM TLDP is ∼325 GHz, which is higher than the simulated bandwidth of the LTG GaAs MSM VMDP with an open-circuit input end (∼240 GHz) and is almost comparable to the simulated bandwidth of an input-terminated LTG GaAs MSM VMDP (∼330 GHz). This proposed method can be applied to the design of high-bandwidth distributed photodetectors for radio-frequency photonic systems and optoelectronic generation of high-power microwaves and millimeter waves.
AB - We present the theory and design of a tapered line distributed photodetector (TLDP). In the previously demonstrated velocity-matched distributed photodetector (VMDP), high electrical bandwidth is achieved by proper termination in the input end to absorb reverse traveling waves, sacrificing one-half of the quantum efficiency. By utilizing the tapered line structure and phase matching between optical waves and microwaves in our analyzed structure, a traveling-wave photodetector is more realizable and ultrahigh bandwidth can be attained due to removal of the extra input dummy load that sacrifices one-half of the total quantum efficiency. To investigate the advantages of TLDP over VMDP, we calculate their electrical bandwidth performances by using an analytic photodistributed current model. We adopted low-temperature-grown (LTG) GaAs-based metal-semiconductor-metal (MSM) traveling-wave photodetectors as example unit active devices in the analytic bandwidth calculation for their high-speed and high-power performances. Both VMDP and TLDP in our simulation are assumed to be transferred onto glass substrates, which would achieve high microwave velocity/impedance and make radiation loss negligible. The simulated bandwidth of a properly designed LTG GaAs MSM TLDP is ∼325 GHz, which is higher than the simulated bandwidth of the LTG GaAs MSM VMDP with an open-circuit input end (∼240 GHz) and is almost comparable to the simulated bandwidth of an input-terminated LTG GaAs MSM VMDP (∼330 GHz). This proposed method can be applied to the design of high-bandwidth distributed photodetectors for radio-frequency photonic systems and optoelectronic generation of high-power microwaves and millimeter waves.
KW - Distributed photodetector
KW - High-bandwidth photodetector
KW - High-power photodetector
KW - Low-temperature-grown GaAs
KW - Metal-semiconductor-metal (MSM) photodetector
KW - Tapered line
KW - Traveling-wave photodetector
KW - Ultra-high-speed photodetector
UR - http://www.scopus.com/inward/record.url?scp=0036875626&partnerID=8YFLogxK
U2 - 10.1109/JLT.2002.806331
DO - 10.1109/JLT.2002.806331
M3 - 期刊論文
AN - SCOPUS:0036875626
SN - 0733-8724
VL - 20
SP - 1942
EP - 1950
JO - Journal of Lightwave Technology
JF - Journal of Lightwave Technology
IS - 11
ER -