摘要
Pre-strained nanomembranes with four embedded quantum wells(QWs) are rolled up into threedimensional(3D) tubular QW infrared photodetectors(QWIPs),which are based on the QW intersubband transition(ISBT).A redshift of ~0.42 meV in photocurrent response spectra is observed and attributed to two strain contributions due to the rolling of the pre-strained nanomembranes.One is the overall strain that mainly leads to a redshift of ~0.5 meV,and the other is the strain gradient which results in a very tiny variation.The blue shift of the photocurrent response spectra with the external bias are also observed as quantum-confined Stark effect(QCSE)in the ISBT.
Pre-strained nanomembranes with four embedded quantum wells(QWs) are rolled up into threedimensional(3D) tubular QW infrared photodetectors(QWIPs),which are based on the QW intersubband transition(ISBT).A redshift of ~0.42 meV in photocurrent response spectra is observed and attributed to two strain contributions due to the rolling of the pre-strained nanomembranes.One is the overall strain that mainly leads to a redshift of ~0.5 meV,and the other is the strain gradient which results in a very tiny variation.The blue shift of the photocurrent response spectra with the external bias are also observed as quantum-confined Stark effect(QCSE)in the ISBT.
基金
Project supported by the Natural Science Foundation of China(Nos.51322201,61575213)
the Shanghai Municipal Science and Technology Commission(No.14JC 1400200)