Related Experiment Video
Updated: Oct 11, 2026

Scalable Quantum Integrated Circuits on Superconducting Two-Dimensional Electron Gas Platform
Published on: August 2, 2019
Nonreciprocal Perfect Coulomb Drag in Electron-Hole Bilayers: Coherent Exciton Superflow as a Diode
Jun-Xiao Hui1, Qing-Dong Jiang1,2
1Shanghai Jiao Tong University, Tsung-Dao Lee Institute and School of Physics and Astronomy, Pudong, Shanghai, 201210, China.
Abstract:
Distinguishing an exciton condensate from an excitonic gas or insulator remains a fundamental challenge, as both phases feature bound electron-hole pairs but differ only by the emergence of macroscopic phase coherence. Here, we theoretically propose that a spin-orbit-coupled bilayer system can host a finite-momentum exciton condensate exhibiting a nonreciprocal perfect Coulomb drag-the coherent-exciton diode effect. This effect arises from the simultaneous breaking of inversion and time-reversal symmetries in the exciton condensate, resulting in direction-dependent critical counterflow currents. The resulting nonreciprocal perfect Coulomb drag provides a clear and unambiguous transport signature of phase-coherent exciton condensation, offering a powerful and experimentally accessible approach to identify, probe, and control exciton superfluidity in solid-state platforms.
More Related Videos
11:33All-electronic Nanosecond-resolved Scanning Tunneling Microscopy: Facilitating the Investigation of Single Dopant Charge Dynamics
Published on: January 19, 2018
08:04Excitonic Hamiltonians for Calculating Optical Absorption Spectra and Optoelectronic Properties of Molecular Aggregates and Solids
Published on: May 27, 2020
Related Concept Videos
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
Coulomb's Law and The Principle of Superposition
The Principle of Superposition answers the question. Yes, Coulomb's Law applies to each pair of charges, and the net force on each charge is the vector sum of the...
Biasing of P-N Junction
In equilibrium, no external voltage is applied across the p-n junction. The depletion region is formed at the junction interface due to the diffusion of carriers, which leaves behind charged dopants, acceptors on the p-side, and donors on the n-side. These immobile charges create an electric field that prevents further diffusion of carriers. The related energy band...
Electrostatic Boundary Conditions in Dielectrics
Consider a case where both the mediums across a boundary are two different dielectric materials. Recall that the electric field and electric displacement are proportional and related through the material's permittivity.
Carrier Transport
Drift Current:
The drift of charge carriers is started by an external electric field (E). Charged particles, such as electrons and holes, experience an acceleration between collisions with lattice atoms. For electrons, this results in a drift velocity (vd) given by: