Computer modelling of thorium doping in LiCaAlF<sub>6</sub>and LiSrAlF<sub>6</sub>: application to the development of solid state optical frequency devices

Jackson, Robert A.; Amaral, Jomar B.; Valério, Mário E.G.; DeMille, David; Hudson, Eric R.

doi:10.1088/0953-8984/21/32/325403

Cited by 20 publications

(17 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…229 Th 4þ ions are expected to substitute at the Ca 2þ location in LiCAF along with two F À interstitials for charge compensation [38]. Because of the octahedral symmetry of the Ca site, electric field gradient effects will be minimized.…”

mentioning

confidence: 99%

Constraining the Evolution of the Fundamental Constants with a Solid-State Optical Frequency Reference Based on theTh229Nucleus

et al. 2010

View full text Add to dashboard Cite

We describe a novel approach to directly measure the energy of the narrow, low-lying isomeric state in 229Th. Since nuclear transitions are far less sensitive to environmental conditions than atomic transitions, we argue that the 229Th optical nuclear transition may be driven inside a host crystal with a high transition Q. This technique might also allow for the construction of a solid-state optical frequency reference that surpasses the short-term stability of current optical clocks, as well as improved limits on the variability of fundamental constants. Based on analysis of the crystal lattice environment, we argue that a precision (short-term stability) of 3×10(-17)<Δf/f<1×10(-15) after 1 s of photon collection may be achieved with a systematic-limited accuracy (long-term stability) of Δf/f∼2×10(-16). Improvement by 10(2)-10(3) of the constraints on the variability of several important fundamental constants also appears possible.

show abstract

mentioning

confidence: 99%

Constraining the Evolution of the Fundamental Constants with a Solid-State Optical Frequency Reference Based on theTh229Nucleus

et al. 2010

View full text Add to dashboard Cite

show abstract

“…In the 229 Th:LiCaAlF 6 crystal the leading contribution to EFG at the Th 4+ ion site comes from F − ions, which compensate the extra charge 2 + . These ions are located in interstitial sites in the vicinity of Th 4+ [21,22]. An estimation gives φ zz ≃ −10 18 V cm −2 at the Th 4+ site in 229 Th:LiCaAlF 6 .…”

mentioning

confidence: 99%

Proposal for a Nuclear Gamma-Ray Laser of Optical Range

2011

View full text Add to dashboard Cite

A possibility of the amplification of the 7.6 eV γ radiation by the stimulated γ emission of the ensemble of the (229m)Th isomeric nuclei in a host dielectric crystal is proved theoretically. This amplification is a result of (1) the excitation of a large number of (229m)Th isomers by laser radiation, (2) the creation of the inverse population of nuclear levels in a cooled sample owing to the interaction of thorium nuclei with the crystal electric field or with an external magnetic field, (3) the emission or absorption of the optical photons by thorium nuclei in the crystal without recoil, and (4) the nuclear spin relaxation through the conduction electrons of the metallic covering.

show abstract

“…The crystal-lattice nuclear clock approach makes important use of a suppression of the internal-conversion decay of the isomeric state by choosing large-band-gap crystals like, e.g., MgF 2 , CaF 2 or LiSrAlF 6 as host materials for the 229 Th ions, which possess a 4+ charge state due to their position in the crystal lattice [79,85,127,150,262,287]. In this way, the radiative decay of 229m Th will become observable and no shortening of the isomer's lifetime due to internal conversion occurs, leading to a reduction of the transition linewidth and thus to a higher sensitivity for any laser detuning.…”

Section: Stability Performance Of a Crystal-lattice Clockmentioning

confidence: 99%

“…These crystals are expected to also provide the basis for solid-state nuclear frequency standards [179]. Significant progress has been made in crystal development and theoretical understanding [9,79,85,107,127,150,178,262,287,316,335,337]. Two experimental results using synchrotron radiation have been reported, which were, however, negative: the first one performed by UCLA, using the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory [151,152] the second one performed by the Technical University of Vienna, using the Metrology Light Source (MLS) in Berlin, Germany [338].…”

Section: Population Via Direct Excitationmentioning

confidence: 99%

The $$^{229}$$Th isomer: prospects for a nuclear optical clock

Wense

2020

Eur. Phys. J. A

View full text Add to dashboard Cite

The proposal for the development of a nuclear optical clock has triggered a multitude of experimental and theoretical studies. In particular the prediction of an unprecedented systematic frequency uncertainty of about $$10^{-19}$$ 10 - 19 has rendered a nuclear clock an interesting tool for many applications, potentially even for a re-definition of the second. The focus of the corresponding research is a nuclear transition of the $$^{229}$$ 229 Th nucleus, which possesses a uniquely low nuclear excitation energy of only $$8.12\pm 0.11$$ 8.12 ± 0.11 eV ($$152.7\pm 2.1$$ 152.7 ± 2.1 nm). This energy is sufficiently low to allow for nuclear laser spectroscopy, an inherent requirement for a nuclear clock. Recently, some significant progress toward the development of a nuclear frequency standard has been made and by today there is no doubt that a nuclear clock will become reality, most likely not even in the too far future. Here we present a comprehensive review of the current status of nuclear clock development with the objective of providing a rather complete list of literature related to the topic, which could serve as a reference for future investigations.

show abstract

Computer modelling of thorium doping in LiCaAlF₆and LiSrAlF₆: application to the development of solid state optical frequency devices

Cited by 20 publications

References 11 publications

Constraining the Evolution of the Fundamental Constants with a Solid-State Optical Frequency Reference Based on theTh229Nucleus

Constraining the Evolution of the Fundamental Constants with a Solid-State Optical Frequency Reference Based on theTh229Nucleus

Proposal for a Nuclear Gamma-Ray Laser of Optical Range

The $$^{229}$$Th isomer: prospects for a nuclear optical clock

Contact Info

Product

Resources

About

Computer modelling of thorium doping in LiCaAlF6and LiSrAlF6: application to the development of solid state optical frequency devices

Cited by 20 publications

References 11 publications

Constraining the Evolution of the Fundamental Constants with a Solid-State Optical Frequency Reference Based on theTh229Nucleus

Constraining the Evolution of the Fundamental Constants with a Solid-State Optical Frequency Reference Based on theTh229Nucleus

Proposal for a Nuclear Gamma-Ray Laser of Optical Range

The $$^{229}$$Th isomer: prospects for a nuclear optical clock

Contact Info

Product

Resources

About

Computer modelling of thorium doping in LiCaAlF₆and LiSrAlF₆: application to the development of solid state optical frequency devices