J Biomol NMR (2017) 69:181–182
Nicolaas Bloembergen: a pioneer in magnetic resonance and in
maser and laser physics
· Rolf Boelens
· Claudio Luchinat
© Springer Science+Business Media B.V. 2017
In particular his work on nonlinear optics earned him the
Nobel Prize in Physics in 1981 (https://www.nobelprize.org/
Nico Bloembergen was born in 1920 in The Netherlands.
He started his study of physics in 1938 at Utrecht University
mainly because Utrecht was conveniently close to Bilthoven,
the town where he lived. He passed his master’s exam in
1943 just a few weeks before the German army, that occu-
pied Holland during World War II, closed the university.
As conditions for his PhD research would be very poor in
Holland during and just after the war, he moved in 1946
to Harvard University, where he was accepted as the ﬁrst
PhD student of Edward Purcell. Of course, NMR in con-
densed matter had just been discovered by Purcell and his
co-workers Pound and Torrey (and independently by Felix
Bloch at Stanford). For their discoveries Purcell and Bloch
would share the Nobel Prize in Physics in 1952.
At Harvard, Bloembergen started to work at both experi-
mental and theoretical aspects of NMR (he considered him-
self an experimentalist). However, his main accomplishment
during the years 1946–1948 was his ground-breaking work
on nuclear spin relaxation, that became known as the BPP
theory (after the authors Bloembergen, Purcell, and Pound).
The Phys Rev paper of 1948 is a citation classic and was for
many years the most cited paper in physics (Bloembergen
et al. 1948). This theory explained the “motional narrow-
ing” eﬀect and formed the basis for many of the subsequent
important experimental and theoretical advancements in the
understanding of nuclear and electron relaxation.
In 1947 Bloembergen met Prof. C.J. Gorter during a visit
at Harvard. Gorter was an expert on paramagnetic relaxa-
tion at Leiden University and had made two unsuccessful
attempts to discover NMR (Gorter 1936; Gorter and Broer
1942). Gorter oﬀered him to come to Leiden and ﬁnish his
PhD thesis there. This was attractive to Bloembergen also
Nicolaas Bloembergen, Nobel laureate, died on September
5 at the age of 97 in Tucson, Arizona.
He was a true pioneer in two research areas: NMR spectros-
copy, where he was the ﬁrst to describe the fundamentals
of nuclear spin relaxation, and in maser and laser physics.
Historical perspectives can be found in Bloembergen (1994,
This obituary will also appear in the AMPERE bulletin (https://
* Rob Kaptein
Department of Chemistry, Utrecht University, Padualaan 8,
3584 CH Utrecht, The Netherlands
CERM and Department of Chemistry, University
of Florence, Via Luigi Sacconi 6, 50019 Sesto Fiorentino,