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Joined 2026-09-21 Message
Incoming links: John L. Hall
Nobel Prize in Physics in 2005 2026-10-18
One half went to Roy J. Glauber for contributions to the quantum theory of optical coherence. One quarter each went to John L. Hall and Theodor W. Hänsch for developing precision laser spectroscopy, including the optical frequency comb technique.[ref]
The Nobel Prize in Physics 2005 by Nobel Prize Outreach. Individual official 2005 summary: Glauber one half for quantum optical coherence; Hall and Hänsch one quarter each for laser-based precision spectroscopy including frequency combs.
Optical frequency comb 2026-10-18
An optical frequency comb has evenly spaced optical spectral lines, or teeth. A mode-locked laser supplies short optical pulses at repetition frequency , the tooth spacing. The carrier-envelope offset frequency positions the whole ruler:Only teeth within the emitted optical spectrum are present; the extrapolated intercept need not be an emitted tooth.[ref]
Passion for Precision by Theodor W. Hänsch. Passion for Precision, p.157: tooth relation
The achievement associated with John L. Hall and Theodor W. Hänsch is a practical bridge between optical frequencies and countable electronic frequencies. Instead of constructing a separate chain of lasers for each optical measurement, a broad comb supplies many linked reference teeth. Stable lasers, short optical pulses and strong nonlinear optics in optical fibers came together around 1999–2000.[ref]
Nobel Lecture: Defining and measuring optical frequencies by John L. Hall. Nobel Lecture: Defining and measuring optical frequencies, pp.1288–1291: chains and comb development