Photons and Atoms Approaching Equilibrium

The latest snowstorm is wreaking some havoc on my plans for the day, which means I’m going to lift another question and answer from the Physics Stack Exchange, with some modification. This one is a question about thermal radiation: What are the quantum mechanisms behind the emission and absorption of thermal radiation at and below… Continue reading Photons and Atoms Approaching Equilibrium

Physics Announcements: New Forum, Undergraduate Research Session

I was at a meeting of the Committee on Informing the Public of the American Physical Society at the tail end of last week, so it seems appropriate to post a couple of APS-related announcements here on my return: 1) The APS has just created a Forum on Outreach and Engaging the Public. You may… Continue reading Physics Announcements: New Forum, Undergraduate Research Session

Poll: Top Physics Story of 2010?

It’s the last week of the (calendar) year, which means it’s a good time to recap the previous twelve months worth of scientific news. Typically, publications like Physics World will publish a list of top ten physics stories of 2010, but we’re all Web 2.0 these days, so it seems more appropriate to put this… Continue reading Poll: Top Physics Story of 2010?

How Does Light Travel Through Glass?

I’ve mentioned before that I’m answering the occasional question over at the Physics Stack Exchange site, a crowd-sourced physics Q&A. When I’m particularly pleased with a question and answer, I’ll be promoting them over here like, well, now. Yesterday, somebody posted this question: Consider a single photon (λ=532 nm) traveling through a plate of perfect… Continue reading How Does Light Travel Through Glass?

Dance of the Photons by Anton Zeilinger

I hadn’t heard anything about Dance of the Photons: From Einstein to Quantum Teleportation before it turned up in my mailbox, courtesy of some kind publicist at Farrar, Straus, and Giroux, otherwise I would’ve been eagerly anticipating it. Anton Zeilinger is a name to conjure with in quantum optics, having built an impressive career out… Continue reading Dance of the Photons by Anton Zeilinger

Interference of Independent Photon Beams: The Pfleegor-Mandel Experiment

Earlier this week, I talked about the technical requirements for taking a picture of an interference pattern from two independent lasers, and mentioned in passing that a 1967 experiment by Pfleegor and Mandel had already shown the interference effect. Their experiment was clever enough to deserve the ResearchBlogging Q&A treatment, though, so here we go:… Continue reading Interference of Independent Photon Beams: The Pfleegor-Mandel Experiment

How Do You See Interference Between Independent Lasers?

This is adapted from an answer to a question at the Physics Stack Exchange site. The questioner asked: It seems that if the coherence length of a laser is big enough, it is possible to observe a (moving) interference picture by combining them. Is it true? How fast should photo-detectors be for observing of the… Continue reading How Do You See Interference Between Independent Lasers?

The ABC’s of AMO Physics

Over at Confused at a Higher Level, Melissa offers an alphabetical list of essential supplies for a condensed matter experimentalist at a small college. This is a fun idea for back-to-school time, so I’ll steal it, and offer the following alphabetical list of essentials for Atomic, Molecular, and Optical physics at a small college, kind… Continue reading The ABC’s of AMO Physics

Indirect Excitation Control: Ultrafast Quantum Gates for Single Atomic Qubits

Last week, John Baez posted a report on a seminar by Dzimitry Matsukevich on ion trap quantum information issues. In the middle of this, he writes: Once our molecular ions are cold, how can we get them into specific desired states? Use a mode locked pulsed laser to drive stimulated Raman transitions. Huh? As far… Continue reading Indirect Excitation Control: Ultrafast Quantum Gates for Single Atomic Qubits

Bunches and Antibunches of Atoms: Hanbury Brown and Twiss Effects in Ultracold Atoms

Two papers in one post this time out. One of these was brought to my attention by Joerg Heber, the other I was reminded of when checking some information for last week’s mathematical post on photons. They fit extremely well together though, and both relate to the photon correlation stuff I was talking about last… Continue reading Bunches and Antibunches of Atoms: Hanbury Brown and Twiss Effects in Ultracold Atoms