TY - JOUR
T1 - Conservation of Hot Thermal Spin-Orbit Population of
2
P Atoms in a Cold Quantum Fluid Environment
AU - Thaler, Bernhard
AU - Meyer, Ralf
AU - Heim, Pascal
AU - Ranftl, Sascha
AU - Pototschnig, Johann V.
AU - Hauser, Andreas W.
AU - Koch, Markus
AU - Ernst, Wolfgang E.
PY - 2019/5/9
Y1 - 2019/5/9
N2 -
The 0.4 K internal temperature of superfluid helium nanodroplets is believed to guarantee a corresponding ground-state population of dopant atoms and molecules inside this cryogenic matrix. We have recorded 6s ← 5p excitation spectra of indium atoms in helium droplets and found two absorption bands separated by about 2000 cm
-
1
, a value close to the spin-orbit (SO) splitting of the In
2
P ground state. The intensities of the bands agree with a thermal population of the
2
P
1/2
and
2
P
3/2
states at 870 K, the temperature of the In pick-up cell. Applying femtosecond pump-probe spectroscopy, we found the same dynamical response of the helium solvation shell after the photoexcitation of the two bands. He-density functional theory simulations of the excitation spectra are in agreement with the bimodal structure. Our findings show that the population of SO levels of hot dopants is conserved after pick-up inside the superfluid droplet. Implications for the interpretation of experiments on molecular aggregates are discussed.
AB -
The 0.4 K internal temperature of superfluid helium nanodroplets is believed to guarantee a corresponding ground-state population of dopant atoms and molecules inside this cryogenic matrix. We have recorded 6s ← 5p excitation spectra of indium atoms in helium droplets and found two absorption bands separated by about 2000 cm
-
1
, a value close to the spin-orbit (SO) splitting of the In
2
P ground state. The intensities of the bands agree with a thermal population of the
2
P
1/2
and
2
P
3/2
states at 870 K, the temperature of the In pick-up cell. Applying femtosecond pump-probe spectroscopy, we found the same dynamical response of the helium solvation shell after the photoexcitation of the two bands. He-density functional theory simulations of the excitation spectra are in agreement with the bimodal structure. Our findings show that the population of SO levels of hot dopants is conserved after pick-up inside the superfluid droplet. Implications for the interpretation of experiments on molecular aggregates are discussed.
UR - http://www.scopus.com/inward/record.url?scp=85065587654&partnerID=8YFLogxK
U2 - 10.1021/acs.jpca.9b02920
DO - 10.1021/acs.jpca.9b02920
M3 - Article
SN - 1089-5639
VL - 123
SP - 3977
EP - 3984
JO - The Journal of Physical Chemistry A
JF - The Journal of Physical Chemistry A
IS - 18
ER -