Related papers: Proposal for a Nuclear Light Source
A low-energy nuclear transition in the isotope thorium-229 has been excited in thorium-doped crystals with laser light. This opens the perspective towards a highly stable and robust solid-state optical nuclear clock. The required laser…
The 7.6-eV-isomer of Thorium-229 offers the opportunity to perform high resolution laser spectroscopy of a nuclear transition. We give a brief review of the investigations of this isomer. The nuclear resonance connecting ground state and…
We study thorium-doped CaF$_2$ crystals as a possible platform for optical spectroscopy of the Th-229 nuclear isomer transition. We anticipate two major sources of background signal that might cover the nuclear spectroscopy signal:…
Thorium-229 is a unique case in nuclear physics: it presents a metastable first excited state Th-229m, just a few electronvolts above the nuclear ground state. This so-called isomer is accessible by VUV lasers, which allows transferring the…
We propose to generate continuous-wave vacuum ultraviolet (VUV) laser light at 148.4 nm using four-wave mixing in cadmium vapor for precision spectroscopy of the Th-229 isomer transition. Due to the large transition matrix elements of…
The most probable candidate for the role of a nuclear optical standard is the 8.338-eV isomer of the 229mTh isotope of the thorium nucleus. Ways of using the resonance properties of the electron shell as an optical resonator to create…
The radiative excitation of the 8.3 eV isomeric state of thorium-229 is an outstanding challenge due to the lack of tunable far-ultraviolet (F-UV) sources. In this work, we propose an efficient two-photon pumping scheme for thorium-229…
The results of experimental studies of the low-energy isomeric state in the $^{229}$Th nucleus are presented. The work is consisted of several stages. During the first stage $^{229}$Th nuclei were excited with the inverse internal…
A possibility of amplification of the 7.6 eV $\gamma$-radiation by the stimulated $\gamma$-emission of the ensemble of the $^{229m}$Th isomeric nuclei in a host dielectric crystal is proved theoretically. This amplification is a result of:…
The nucleus of the radioisotope thorium-229 (${}^{229}$Th) features an isomer with an exceptionally low excitation energy that enables direct laser manipulation of nuclear states. For this reason, it is a leading candidate for use in…
A possibility of the two-photon excitation of an isomeric state in a nucleus of thorium-229 has been discussed. The fluorescence intensity of the excitation is demonstrated to be identical for the irradiation of nuclei with either…
Excitation of the isomeric nuclear state 229m Th in the process of thorium atom irradiation by two-color femtosecond pulse of Ti: Sa laser at the fundamental wavelength and second harmonic is analyzed. It is shown that the rate of isomeric…
With an expected energy of 7.6(5) eV, $^{229}$Th possesses the lowest excited nuclear state in the landscape of all presently known nuclei. The energy corresponds to a wavelength of about 160 nm and would conceptually allow for an optical…
It is proposed to use the isomer ionic ground state $^{229m}$Th$^{4+}$ embedded in transparent crystals for precision determination of unknown neutrino parameters. Isolation from solid environment of the proposed nuclear process, along with…
$^{229}$Th is the only nucleus currently under investigation for the development of a nuclear optical clock (NOC) of ultra-high accuracy. The insufficient knowledge of the first nuclear excitation energy of $^{229}$Th has so far hindered…
The isotope $^{229}$Th is the only nucleus known to possess an excited state $^{229m}$Th in the energy range of a few electron volts, a transition energy typical for electrons in the valence shell of atoms, but about four orders of…
A continuous-wave laser source at 148.4 nm based on second-harmonic generation in randomly quasi-phase matched strontium tetraborate, SrB4O7, is demonstrated. It provides (1.3-0.6+0.7) nW of VUV power in a single pass for an incident UV…
The low-lying isomeric state of $^{229}$Th provides unique opportunities for high-resolution laser spectroscopy of the atomic nucleus. We determine the energy of this isomeric state by taking the absolute energy difference between the…
We consider the excitation of the nuclear transition ^{229g}Th - ^{229m}Th near 7.6 eV in singly ionized thorium via an electronic bridge process. The process relies on the excitation of the electron shell by two laser photons whose sum…
We propose a simple approach to measure the energy of the few-eV isomeric state in Th-229. To this end, U-229 nuclei are doped into VUV-transparent crystals, where they undergo alpha decay into Th-229, and, with a probability of 2%,…