Study of the quantum-confined Stark effect in an unbiased [111]-oriented multi-quantum well semiconductor optical amplifier

Piezoelectric constant temperature dependence in strained [111]-oriented zinc-blende MQW-SOAs

“…In the present analysis, it was assumed the MQW-SOA structure under study is composed of identical QWs, and the F w n and piezoelectric fields are the same in all the wells. Based on these considerations, F w n can be given by [4]…”

“…where ε s is the lattice mismatch strain, and C 11 w , C 12 w , and C 44 w are the elastic stiffness coefficients of the material of the QWs, which can be estimated, as can ε i and ε w , by Vergard's Law [4] . Furthermore, in Eq.…”

“…( 2)], Q q is the elementary charge times 6.2415 × 10 18 eV=J and L iws n is the spatial separation, induced by F w n within the QWs, of the photogenerated electron and hole wave functions. For input powers that, under OCC, produce such a piezoelectric field screening that the 1S e-hh ER energy undergoes a shift of less than 1.0 meV, it can be assumed F wp is strong enough for F w n to induce a spatial separation between the photogenerated electron and hole wave functions close to the largest possible (L w ) [4] . Under these conditions, L iws n ≈ L w .…”

“…Due to the abrupt changes in absorption and refractive index that the quantum-confined Stark effect (QCSE) can potentially induce in a low-dimensional structure, this mechanism has excellent potential for developing ultra-fast all-optical functions for telecommunications systems using strained [111]-oriented zinc-blende multiple quantum well semiconductor optical amplifiers (MQW-SOAs) [1,2] . Indeed, these amplifiers, compared to the massive ones, exhibit higher differential gains, lower noise figures, and, notably, an internal piezoelectric field that is mainly responsible for the QCSE when they are unbiased [3,4] . Therefore, to estimate the temperature dependence of the QCSE in MQW-SOAs and thus be able to use it as a contribution to tune the energy of the excitonic resonances where required for a specific application, it is crucial to determine the temperature dependence of the piezoelectric constant e 14 .…”

Analytical estimation of lifetime of quasi-bound states in iii-v semiconductors quantum well

“…Quantum wells (QW) formed in external electric fields have diverse applications from spintronics [1] to twodimensional superconductivity [2]. QW of III-V semiconductor has a linear or triangular potential profile and is known to show interesting optical properties [3]. In the potential well near the III-V semiconductor heterojunction, charge carriers are trapped in a region a few nanometers in size, from which they can decay across the barrier established by the conduction band discontinuities.…”