Relation between phenomenological few-level models and microscopic theories of the nonlinear optical response of semiconductor quantum wells

Abstract

We analyze a generic atomic few-level model for the third-order ͑ ͑3͒ ͒ optical response of semiconductor quantum wells. The purpose is to seek a good understanding of the physical nature of the model's parameters in terms of the material's microscopic constituents and their motions. The strategy is to bring the algebraic expression of the ͑3͒ interband polarization in the few-level model to a form similar to that derived in microscopic theories. Most importantly, in the coherent limit, we make the "time evolution structure" of the interband polarization in the few-level and microscopic formalisms coincide, whereby the atomic model's parameters can be interpreted microscopically through a comparison of terms of similar structure in the two formalisms. We also discuss how the conclusion of this comparison can be changed by the introduction of phenomenological dephasing and decay into both theories.

Coherent two-exciton dynamics measured using two-quantum rephasing two-dimensional electronic spectroscopy

“…The former treat the quantum well as a simple few-level system (meaning that it begins with the same isolated states used in the sum-over-states approach) and then includes phenomenological terms to represent the MBIs, including any required binding energies, while the latter considers only the band structure of the semiconductor quantum well and the Coulomb coupling to generate the excitons, the multiexcitons, and the MBIs. The differences and similarities between the two approaches have been detailed elsewhere [30].…”

“…5, where all three diagrams contain two-quantum coherences (|g HH|) during the scanned time period In this simulation, we assumed that the dipole moments connecting the various states are equal [30].…”

“…We used a value of 15 Debye for the transition dipole moments between states [30]. The LFE parameter value (unitless) and the EID and EIS parameter values γ ′ and ω ′ (THz/m 3 )…”

Optical instabilities in semiconductor quantum‐well systems driven by phase‐space filling

“…(We note that PSF contributions and the Coulomb terms, derived here from a microscopic theory [29] can be related to simple few-level models as outlined in Ref. [30].) The nonlinear pump equation for p p ± (not shown) involves the same nonlinear processes.…”

Polarized Optical Two-dimensional Fourier Transform Spectroscopy of Semiconductors

“…EID and EIS in the phenomenological model correspond to the renormalization of the imaginary and real parts of the exciton self-energy, respectively, therefore they are not independent parameters in the microscopic theory. The relation between phenomenological few-level models and microscopic semiconductor theories has been discussed [127].…”