國立高雄大學圖資館 |

Language: English

Back

Buffer gas loading and evaporative c...

Harvard University.

Buffer gas loading and evaporative cooling in the multi-partial-wave regime.

Record Type:	Electronic resources : Monograph/item
Title/Author:	Buffer gas loading and evaporative cooling in the multi-partial-wave regime.
Author:	Nguyen, Scott Vinh.
Description:	153 p.
Notes:	Adviser: John Morrissey Doyle.
Notes:	Source: Dissertation Abstracts International, Volume: 67-05, Section: B, page: 2611.
Contained By:	Dissertation Abstracts International67-05B.
Subject:	Physics, Atomic.
Online resource:	http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3217838
ISBN:	9780542693557

Buffer gas loading and evaporative cooling in the multi-partial-wave regime.
Nguyen, Scott Vinh.

Buffer gas loading and evaporative cooling in the multi-partial-wave regime. - 153 p.

Adviser: John Morrissey Doyle.

Thesis (Ph.D.)--Harvard University, 2006.

This thesis describes the study of collisions in the multi-partial-wave regime relevant to the buffer gas cooling and trapping of atoms. A quantitative model is formulated to describe the dynamics of evaporative cooling and is used to infer elastic and inelastic collision rate constants of g el = 2.15(+2.5, -1.2) x 10-10 cm 3/s and gin = 1.36(+1.2, -0.7) x 10-12 cm3/s between two chromium atoms in the temperature range of 0.02-1 K and explains a long standing discrepancy between theory and experiment. Magnetic trapping is then extended to atomic manganese where up to 2 x 1012 Mn atoms are trapped in all six hyperfine states, allowing for the exploration of the role of the hyperfine interaction in spin-exchange collisions. In addition, we simultaneously trap a 55Mn-52Cr mixture and measure an inter-species inelastic rate constant of gMn,cr = 1.5 (+/-0.2) +/- 10-13 cm3/s. Demonstrating that buffer gas loading is a viable alternative to laser cooling, we have magnetically trapped and evaporatively cooled metastable helium in large numbers. 10 11 4He* atoms are trapped at an initial temperature of 400 mK and evaporatively cooled into the ultracold regime, resulting in a cloud of 2 +/- 0.5 x 109 atoms at 1.4 +/- 0.2 mK and an increase in phase space density of 5 orders of magnitude. Efficient evaporation indicates low collisional loss for 4He* in both the ultracold and multi-partial-wave regime, in agreement with theory.

ISBN: 9780542693557Subjects--Topical Terms:

227348
Physics, Atomic.

Buffer gas loading and evaporative cooling in the multi-partial-wave regime.
LDR:02382nmm _2200253 _450 001 180547
005 20080111103734.5
008 090528s2006 eng d
020 $a 9780542693557
035 $a 00311571
040 $a UMI $c UMI
100 0 $a Nguyen, Scott Vinh. $3 264121
245 1 0 $a Buffer gas loading and evaporative cooling in the multi-partial-wave regime.
300 $a 153 p.
500 $a Adviser: John Morrissey Doyle.
500 $a Source: Dissertation Abstracts International, Volume: 67-05, Section: B, page: 2611.
502 $a Thesis (Ph.D.)--Harvard University, 2006.
520 # $a This thesis describes the study of collisions in the multi-partial-wave regime relevant to the buffer gas cooling and trapping of atoms. A quantitative model is formulated to describe the dynamics of evaporative cooling and is used to infer elastic and inelastic collision rate constants of g el = 2.15(+2.5, -1.2) x 10-10 cm 3/s and gin = 1.36(+1.2, -0.7) x 10-12 cm3/s between two chromium atoms in the temperature range of 0.02-1 K and explains a long standing discrepancy between theory and experiment. Magnetic trapping is then extended to atomic manganese where up to 2 x 1012 Mn atoms are trapped in all six hyperfine states, allowing for the exploration of the role of the hyperfine interaction in spin-exchange collisions. In addition, we simultaneously trap a 55Mn-52Cr mixture and measure an inter-species inelastic rate constant of gMn,cr = 1.5 (+/-0.2) +/- 10-13 cm3/s. Demonstrating that buffer gas loading is a viable alternative to laser cooling, we have magnetically trapped and evaporatively cooled metastable helium in large numbers. 10 11 4He* atoms are trapped at an initial temperature of 400 mK and evaporatively cooled into the ultracold regime, resulting in a cloud of 2 +/- 0.5 x 109 atoms at 1.4 +/- 0.2 mK and an increase in phase space density of 5 orders of magnitude. Efficient evaporation indicates low collisional loss for 4He* in both the ultracold and multi-partial-wave regime, in agreement with theory.
590 $a School code: 0084.
650 # 0 $a Physics, Atomic. $3 227348
690 $a 0748
710 0 # $a Harvard University. $3 212445
773 0 # $g 67-05B. $t Dissertation Abstracts International
790 $a 0084
790 1 0 $a Doyle, John Morrissey, $e advisor
791 $a Ph.D.
792 $a 2006
856 4 0 $u http://libsw.nuk.edu.tw:81/login?url=http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3217838 $z http://pqdd.sinica.edu.tw/twdaoapp/servlet/advanced?query=3217838