Nuclear Spin Temperature and Deuterium-to-Hydrogen Ratio of Methane in Comet C/2001 Q4 (NEAT)

2005 ◽  
Vol 623 (1) ◽  
pp. L49-L52 ◽  
Author(s):  
Hideyo Kawakita ◽  
Jun-ichi Watanabe ◽  
Reiko Furusho ◽  
Tetsuharu Fuse ◽  
Daniel C. Boice
Keyword(s):  
Nuclear Spin ◽  
Spin Temperature

Nuclear spin temperature of ammonia in Comet 9P/Tempel 1 before and after the Deep Impact event

Icarus ◽  
2007 ◽  
Vol 191 (2) ◽  
pp. 513-516 ◽  
Author(s):  
Hideyo Kawakita ◽  
Emmanuel Jehin ◽  
Jean Manfroid ◽  
Damien Hutsemékers
Keyword(s):  
Nuclear Spin ◽  
Impact Event ◽  
Spin Temperature ◽  
Deep Impact ◽  
Before And After

scholarly journals Nuclear spin temperature reversal via continuous radio-frequency driving

2021 ◽  
Vol 103 (8) ◽  
Author(s):  
Pablo R. Zangara ◽  
Daniela Pagliero ◽  
Ashok Ajoy ◽  
Rodolfo H. Acosta ◽  
Jeffrey A. Reimer ◽  
...  
Keyword(s):  
Radio Frequency ◽  
Nuclear Spin ◽  
Spin Temperature

Nuclear spin temperature of ammonia in Comet 9P/Tempel 1 before and after the Deep Impact event

Icarus ◽  
2007 ◽  
Vol 187 (1) ◽  
pp. 272-275 ◽  
Author(s):  
Hideyo Kawakita ◽  
Emmanuel Jehin ◽  
Jean Manfroid ◽  
Damien Hutsemékers
Keyword(s):  
Nuclear Spin ◽  
Impact Event ◽  
Spin Temperature ◽  
Deep Impact ◽  
Before And After

scholarly journals Ultra-deep optical cooling of coupled nuclear spin-spin and quadrupole reservoirs in a GaAs/(Al,Ga)As quantum well

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Mladen Kotur ◽  
Daniel O. Tolmachev ◽  
Valentina M. Litvyak ◽  
Kirill V. Kavokin ◽  
Dieter Suter ◽  
...  
Keyword(s):  
Quantum Well ◽  
Nuclear Spin ◽  
Optical Pumping ◽  
Larmor Frequency ◽  
Spin Splitting ◽  
Magnetic Field Direction ◽  
Nuclear Spins ◽  
Spin Temperature ◽  
Adiabatic Demagnetization ◽  
Selective Cooling

AbstractThe physics of interacting nuclear spins in solids is well interpreted within the nuclear spin temperature concept. A common approach to cooling the nuclear spin system is adiabatic demagnetization of the initial, optically created, nuclear spin polarization. Here, the selective cooling of 75As spins by optical pumping followed by adiabatic demagnetization in the rotating frame is realized in a nominally undoped GaAs/(Al,Ga)As quantum well. The lowest nuclear spin temperature achieved is 0.54 μK. The rotation of 6 kG strong Overhauser field at the 75As Larmor frequency of 5.5 MHz is evidenced by the dynamic Hanle effect. Despite the presence of the quadrupole induced nuclear spin splitting, it is shown that the rotating 75As magnetization is uniquely determined by the spin temperature of coupled spin-spin and quadrupole reservoirs. The dependence of heat capacity of these reservoirs on the external magnetic field direction with respect to crystal and structure axes is investigated.

scholarly journals Breakdown of the nuclear-spin-temperature approach in quantum-dot demagnetization experiments

2009 ◽  
Vol 5 (6) ◽  
pp. 407-411 ◽  
Author(s):  
P. Maletinsky ◽  
M. Kroner ◽  
A. Imamoglu
Keyword(s):  
Quantum Dot ◽  
Nuclear Spin ◽  
Spin Temperature

Dynamic Polarization in Single Crystals of CaF2 Containing H Atoms as Paramagnetic Impurities

1969 ◽  
Vol 24 (11) ◽  
pp. 1737-1745
Author(s):  
P. Zegers
Keyword(s):  
Single Crystals ◽  
Spin System ◽  
Nuclear Spin ◽  
Microwave Power ◽  
Modulation Frequency ◽  
Thermal Contact ◽  
Dynamic Polarization ◽  
Spin Temperature ◽  
Nuclear Spin System ◽  
Paramagnetic Centres

Formulae for dynamic polarization in solids having an inhomogeneous electron spin system and a nuclear spin system which can be described by one single spin temperature were derived. It was assumed that the spin temperature, in the rotating frame of those paramagnetic centres which fulfil ωe=ω+ωn or ωe = ω-ωn j can increase due to thermal contact with the nuclear spin- system brought about by high microwave power. Field fluctuations, at the positions of the para­magnetic centres, due to relaxation flipping of surrounding nuclei and paramagnetic centres were also taken into account. Formulae obtained for the enhancement and polarization time as a func­tion of microwave power and for the enhancement as a function of field modulation frequency and -amplitude agreed well with the experimental results in CaF2 single crystals containing H atoms.

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