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Updated: Aug 5, 2026
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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
Directional Photocurrent Generated by Quantum Interference Control
Yiming Gong1, Kai Wang1,2, Steven T Cundiff1,3
1University of Michigan, Department of Physics, Ann Arbor, Michigan, 48109, USA.
Physical Review Letters
|July 31, 2026
Summary
Interference between two-photon and three-photon absorption in semiconductors generates a directional electron beam. This phenomenon offers a novel way to create directed currents without an external electric field.
Area of Science:
- Solid State Physics
- Optoelectronics
- Quantum Mechanics
Background:
- Light absorption in semiconductors typically generates photocarriers with equal and opposite momenta, canceling out any net current.
- Interference between different light absorption processes (e.g., one-photon and two-photon) can break this symmetry and induce a current.
Purpose of the Study:
- To investigate the current generation resulting from the interference of two-photon and three-photon absorption in semiconductors.
- To analyze the angular distribution of photocarriers produced by this specific interference mechanism.
Main Methods:
- Theoretical analysis of light-semiconductor interactions involving multiphoton absorption processes.
- Modeling the interference effects between two-photon and three-photon absorption pathways.
- Calculating the momentum distribution of photocarriers generated under these conditions.
Main Results:
- The interference between two-photon and three-photon absorption leads to a net current generation in the semiconductor.
- This process results in a narrower angular spread of photocarriers compared to other interference mechanisms.
- A directional 'beam' of electrons is produced, indicating a preferential direction of motion.
Conclusions:
- The interference of two-photon and three-photon absorption provides a mechanism for generating directed photocurrents in semiconductors.
- This effect allows for the creation of a focused electron beam without the need for an applied electric field.
- Potential applications in novel optoelectronic devices and semiconductor-based current generation.
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