Abstract:
:We demonstrate remote detection of nuclear magnetic resonance (NMR) with a microchip sensor consisting of a microfluidic channel and a microfabricated vapor cell (the heart of an atomic magnetometer). Detection occurs at zero magnetic field, which allows operation of the magnetometer in the spin-exchange relaxation-free (SERF) regime and increases the proximity of sensor and sample by eliminating the need for a solenoid to create a leading field. We achieve pulsed NMR linewidths of 26 Hz, limited, we believe, by the residence time and flow dispersion in the encoding region. In a fully optimized system, we estimate that for 1 s of integration, 7 x 10(13) protons in a volume of 1 mm(3), prepolarized in a 10-kG field, can be detected with a signal-to-noise ratio of approximately 3. This level of sensitivity is competitive with that demonstrated by microcoils in 100-kG magnetic fields, without requiring superconducting magnets.
journal_name
Proc Natl Acad Sci U S Aauthors
Ledbetter MP,Savukov IM,Budker D,Shah V,Knappe S,Kitching J,Michalak DJ,Xu S,Pines Adoi
10.1073/pnas.0711505105subject
Has Abstractpub_date
2008-02-19 00:00:00pages
2286-90issue
7eissn
0027-8424issn
1091-6490pii
0711505105journal_volume
105pub_type
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