Many-body approach to the terahertz response of Wigner molecules in gated nanowire structures

Abstract

In this article, we describe a numerical many-body approach for the description of the electromagnetic response of discrete one-dimensional electronic nanosystems. This approach is based on a recursive method to construct a subset of relevant Slater determinants as a many-body basis for the considered system. In turn, we employ a generalized Floquet theory to calculate the periodic many-body statistical operator for the system which is subject to a periodic time-dependent Hamiltonian. As an application of this method, we propose a THz probe technique to obtain spatially resolved information about the electronic spectra inside gated nanowires. This spectroscopic approach employs a segmented multigate design for the local detection of quantum transitions between few-electron states. The obtained simulation results for the intraband THz response spectrum show fingerprints for the formation of Wigner molecules inside the nanowire in the long channel limit.

Persistent current of Luttinger liquid in one-dimensional ring with weak link: Continuous model studied by configuration interaction and quantum Monte Carlo

“…Our second CI approach, introduced by two of us in Ref. 30 , is called the bucket-brigade CI method (BBCI). After choosing the cutoff for the single-particle energy, we need to asses importance of the remaining Slater determinants in the expansion (52).…”

“…Here we outline the BBCI algorithm 30 . As mentioned in section II.E, we determine the single-particle basis ψ j (x) with the ladder of the single-particle-energy levels ε j and we consider only the first N max levels by introducing the upper energy cutoff as illustrated in the figure 1.…”

Self-consistent ac quantum transport using nonequilibrium Green functions

“…(30) to linear order in the terminal voltage v β , and utilizing Eq. (19) and (20) to substitute for G γ (E + , E) and G < (E + , E). These linearized expressions are summarized in Appendix B. Inserting all relevant terms in Eq.…”

“…In addition, the carrier dynamics in the terahertz (THz) regime was recently probed using time-domain techniques, suggesting that the carrier dynamics is determined by singleparticle rather than plasmonic properties. 9 Theoretically, the problem of time-dependent transport has been approached using a variety of techniques such as scattering matrix theory, [10][11][12][13][14] Floquet methods, [15][16][17][18][19][20][21] Boltzmann transport theory, [22][23][24][25] and nonequilibrium Green Functions (NEGF). Even though the NEGF technique has become to some extent the standard in modeling electronic quantum transport, its application to time-dependent problems has been mainly focused on simplified few-level models, [45][46][47][48][51][52][53][54] or to few-atom one-dimensional wires or molecules.…”

Luttinger liquid and persistent current in a continuous mesoscopic ring with a weak link

“…͑10͔͒ does not change, we cut the expansion by stopping to excite the electrons. Our second approach, introduced by two of us, 15 is the bucket-brigade CI method ͑BBCI͒. After choosing N max one has to assess the importance of the M + 1 determinants in expansion ͑13͒.…”