start-ver=1.4
cd-journal=joma
no-vol=79
cd-vols=
no-issue=
article-no=
start-page=684
end-page=
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2019
dt-pub=20190814
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Raman stimulated neutrino pair emission
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract= A new scheme using macroscopic coherence is proposed to experimentally determine the neutrino mass matrix, in particular the absolute value of neutrino masses, and the mass type, Majorana or Dirac. The proposed process is a collective, coherent Raman scattering followed by neutrino-pair emission from | e of a long lifetime to | g ;.0 + | e .. + i j.i. j + | g with.i. j consisting of six massive neutrino-pairs. Calculated angular distribution has six (i j) thresholds which showup as steps at different angles. Angular locations of thresholds and event rates of the angular distribution make it possible to experimentally determine the smallest neutrino mass to the level of less than several meV, (accordingly all threemasses using neutrino oscillation data), the mass ordering pattern, normal or inverted, and to distinguish whether neutrinos are ofMajorana or Dirac type. Event rates of neutrino-pair emission, when the mechanism of macroscopic coherence amplification works, may become large enough for realistic experiments by carefully selecting certain types of target. The problem to be overcome is macro-coherently amplified quantum electrodynamic background of the process,.0 + | e .. +.2 +.3 + | g , when two extra photons,.2,.3, escape detection. We illustrate our idea using neutral Xe and trivalent Ho ion doped in dielectric crystals.
en-copyright=
kn-copyright=

en-aut-name=HaraHideaki
en-aut-sei=Hara
en-aut-mei=Hideaki
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=YoshimuraMotohiko
en-aut-sei=Yoshimura
en-aut-mei=Motohiko
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

affil-num=1
en-affil=Research Institute for Interdisciplinary ScienceOkayama University
kn-affil=

affil-num=2
en-affil=Research Institute for Interdisciplinary ScienceOkayama University
kn-affil=
END

start-ver=1.4
cd-journal=joma
no-vol=6
cd-vols=
no-issue=1
article-no=
start-page=013005
end-page=
dt-received=
dt-revised=
dt-accepted=
dt-pub-year=2024
dt-pub=20240103
dt-online=
en-article=
kn-article=
en-subject=
kn-subject=
en-title=
kn-title=Periodic superradiance in an Er:YSO crystal
en-subtitle=
kn-subtitle=
en-abstract=
kn-abstract=We observed periodic optical pulses from an Er:YSO crystal during irradiating with a continuous-wave excitation laser. We refer to this phenomenon as "periodic superradiance." This periodicity can be understood qualitatively by a simple model, in which a cyclic process of a continuous supply of population inversion and a sudden burst of superradiance is repeated. The excitation power dependences of peak interval and the pulse area can be interpreted with our simple model. In addition, the linewidth of superradiance is much narrower than an inhomogeneous broadening in a crystal. This result suggests that only Er3+ ions in a specific environment are involved in superradiance.
en-copyright=
kn-copyright=

en-aut-name=HaraHideaki
en-aut-sei=Hara
en-aut-mei=Hideaki
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=1
ORCID=

en-aut-name=HanJunseok
en-aut-sei=Han
en-aut-mei=Junseok
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=2
ORCID=

en-aut-name=ImaiYasutaka
en-aut-sei=Imai
en-aut-mei=Yasutaka
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=3
ORCID=

en-aut-name=SasaoNoboru
en-aut-sei=Sasao
en-aut-mei=Noboru
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=4
ORCID=

en-aut-name=YoshimiAkihiro
en-aut-sei=Yoshimi
en-aut-mei=Akihiro
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=5
ORCID=

en-aut-name=YoshimuraKoji
en-aut-sei=Yoshimura
en-aut-mei=Koji
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=6
ORCID=

en-aut-name=YoshimuraMotohiko
en-aut-sei=Yoshimura
en-aut-mei=Motohiko
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=7
ORCID=

en-aut-name=MiyamotoYuki
en-aut-sei=Miyamoto
en-aut-mei=Yuki
kn-aut-name=
kn-aut-sei=
kn-aut-mei=
aut-affil-num=8
ORCID=

affil-num=1
en-affil=Research Institute for Interdisciplinary Science, Okayama University
kn-affil=

affil-num=2
en-affil=Research Institute for Interdisciplinary Science, Okayama University
kn-affil=

affil-num=3
en-affil=Research Institute for Interdisciplinary Science, Okayama University
kn-affil=

affil-num=4
en-affil=Research Institute for Interdisciplinary Science, Okayama University
kn-affil=

affil-num=5
en-affil=Research Institute for Interdisciplinary Science, Okayama University
kn-affil=

affil-num=6
en-affil=Research Institute for Interdisciplinary Science, Okayama University
kn-affil=

affil-num=7
en-affil=Research Institute for Interdisciplinary Science, Okayama University
kn-affil=

affil-num=8
en-affil=Research Institute for Interdisciplinary Science, Okayama University
kn-affil=
END