Related Experiment Video
Updated: Aug 23, 2026

Nanofabrication of Gate-defined GaAs/AlGaAs Lateral Quantum Dots
Published on: November 1, 2013
Influence of branch points in the complex plane on the transmission through double quantum dots
1Max-Planck-Institut für Physik komplexer Systeme, D-01187 Dresden, Germany. rotter@mpipks-dresden.mpg.de
Abstract:
We consider single-channel transmission through a double quantum dot system consisting of two single dots that are connected by a wire and coupled each to one lead. The system is described in the framework of the S matrix theory by using the effective Hamiltonian of the open quantum system. It consists of the Hamiltonian of the closed system (without attached leads) and a term that accounts for the coupling of the states via the continuum of propagating modes in the leads. This model allows one to study the physical meaning of branch points in the complex plane. They are points of coalesced eigenvalues and separate the two scenarios with avoided level crossings and without any crossings in the complex plane. They influence strongly the features of transmission through double quantum dots.
Related Concept Videos
The de Broglie Wavelength
Induced Electric Dipoles
Since the absolute value of potential energy holds no physical meaning, its zero value can be chosen as per...
Debye–Huckel–Onsager Conductance Equation
Electric Potential Energy of Two Point Charges
Divergence and Curl of Electric Field
Transmission-Line Differential Equations
Line Section Model
A circuit representing a line section of length Δx helps in understanding the transmission line parameters. The voltage V(x) and current i(x) are measured from the...

