Cryogenic Differential Amplifier for NMR Applications.
J Low Temp Phys
; 195(1): 72-80, 2019.
Article
em En
| MEDLINE
| ID: mdl-31073248
ABSTRACT
We have designed and characterized a cryogenic amplifier for use in 3 He NMR spectrometry. The amplifier, with a power consumption of â¼ 2.5 mW, works at temperatures down to 4 K. It has a high-impedance input for measuring a signal from NMR resonant circuit, and a 50 Ω differential input which can be used for pick-up compensation and gain calibration. At 4.2 K, the amplifier has a voltage gain of 45, output resistance 146 Ω and a 4.4 MHz bandwidth starting from DC. At 1 MHz, the voltage and current noise amount to 1.3 nV / Hz and 12 fA / Hz , respectively, which yields an optimal source impedance of â¼ 100 k Ω .
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Idioma:
En
Revista:
J Low Temp Phys
Ano de publicação:
2019
Tipo de documento:
Article
País de afiliação:
Finlândia