Search research articles

ABOUT JoVE

Overview Leadership Blog JoVE Help Center

AUTHORS

Publishing Process Editorial Board Scope & Policies Peer Review FAQ Submit

LIBRARIANS

Testimonials Subscriptions Access Resources Library Advisory Board FAQ

RESEARCH

JoVE Journal Methods Collections JoVE Encyclopedia of Experiments Archive

EDUCATION

JoVE Core JoVE Business JoVE Science Education JoVE Lab Manual Faculty Resource Center Faculty Site

Terms & Conditions of Use

Related Concept Videos

Biasing of P-N Junction

Biasing of P-N Junction

The operation of a p-n junction diode involves various biasing conditions, including forward bias, reverse bias, and equilibrium.
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...

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by

Same author

Single-shot wide-field biochemical imaging at 1 kHz frame rate.

Proceedings of the National Academy of Sciences of the United States of America·2026

Same author

From vibrations to function: Spectroscopic detection and quantification of π-π stacking in drug-responsive protein complexes.

Science advances·2026

Same author

Laser-damage risk assessment with extreme-event statistics.

Optics express·2026

Same author

One hundred years of quantum mechanics.

Science (New York, N.Y.)·2025

Same author

Imaging solvated oxygen atoms with a femtosecond laser.

Nature communications·2025

Same author

Quantum-enhanced detection of viral cDNA via luminescence resonance energy transfer using upconversion and gold nanoparticles.

Nanophotonics (Berlin, Germany)·2025

Same journal

Erratum for the Research Article "Detecting supramolecular organic nanoparticles during heat wave".

Science (New York, N.Y.)·2026

Same journal

Local signals, systemic decline.

Science (New York, N.Y.)·2026

Same journal

The mechanics of liver regeneration.

Science (New York, N.Y.)·2026

Same journal

Computing in a memory with physics.

Science (New York, N.Y.)·2026

Same journal

Retraction.

Science (New York, N.Y.)·2026

Same journal

Making time.

Science (New York, N.Y.)·2026

See all related articles

Search research articles

Related Experiment Video

Updated: Jun 4, 2026

20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier

20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier

Published on: July 12, 2017

High-gain backward lasing in air.

Arthur Dogariu¹, James B Michael, Marlan O Scully

¹Mechanical and Aerospace Engineering Department, Princeton University, Princeton, NJ 08544, USA. adogariu@princeton.edu

Science (New York, N.Y.)

|January 29, 2011

Summary

This summary is machine-generated.

Researchers developed a high-gain air laser for remote detection of hazardous gases and explosives. This backward lasing technology enables standoff detection by sampling air as the laser beam returns.

More Related Videos

Construction and Characterization of External Cavity Diode Lasers for Atomic Physics

Construction and Characterization of External Cavity Diode Lasers for Atomic Physics

Published on: April 24, 2014

The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry

The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry

Published on: August 12, 2013

Related Experiment Videos

Last Updated: Jun 4, 2026

20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier

20 mJ, 1 ps Yb:YAG Thin-disk Regenerative Amplifier

Published on: July 12, 2017

Construction and Characterization of External Cavity Diode Lasers for Atomic Physics

Construction and Characterization of External Cavity Diode Lasers for Atomic Physics

Published on: April 24, 2014

The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry

The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry

Published on: August 12, 2013

Area of Science:

Laser physics
Spectroscopy
Remote sensing

Background:

Standoff detection of hazardous gases and explosives is critical.
Existing methods may have limitations in range and sensitivity.

Purpose of the Study:

To develop a remotely pumped, high-gain air laser for backward lasing.
To enable standoff detection of airborne threats.

Main Methods:

Utilizing a focused ultraviolet laser for pumping.
Employing simultaneous resonant two-photon dissociation of molecular oxygen and pumping of atomic oxygen fragments.
Achieving high gain in the near-infrared region.

Main Results:

Demonstrated high gain in a millimeter-length focal zone.
Observed equally strong lasing in both forward and backward directions.
Achieved further backward amplification using prior laser spark dissociation.

Conclusions:

Low-divergence backward air lasing is feasible.
This technology offers promising capabilities for remote detection applications.