中文
相关论文

相关论文: NMR relaxation rates and Knight shifts in MgB2

200 篇论文

We study the nuclear magnetic relaxation rate and Knight shift in the presence of the orbital and quadrupole interactions for three-dimensional Dirac electron systems (e.g., bismuth-antimony alloys). By using recent results of the dynamic…

介观与纳米尺度物理 · 物理学 2017-09-11 Hideaki Maebashi , Tomoki Hirosawa , Masao Ogata , Hidetoshi Fukuyama

We calculated the nuclear spin-lattice relaxation rate in the (Mg,Al)B2 system and found that the orbital relaxation mechanism dominates over the dipolar and Fermi-contact mechanisms in MgB2, whereas in AlB2 due to a smaller density of…

超导电性 · 物理学 2009-11-07 K. D. Belashchenko , V. P. Antropov , S. N. Rashkeev

$^{11}B$ NMR and nuclear spin-lattice relaxation rate (NSLR) are reported at 7.2 Tesla and 1.4 Tesla in powder samples of the intermetallic compound $MgB_2$ with superconducting transition temperature in zero field $T_c$ = 39.2 K. From the…

超导电性 · 物理学 2009-11-07 J. K. Jung , Seung Ho Baek , F. Borsa , S. L. Bud'ko , G. Lapertot , P. C. Canfield

NMR spectra and nuclear spin-lattice relaxation rate $T_1^{-1}$ of $^{11}$B have been measured in superconducting polycrystalline MgB$_{2}$ with $T_C^{ons}\cong 39.5K$. It is shown that $(T_{1}T)^{-1}$ and the Knight shift $K_{s}$ are…

超导电性 · 物理学 2007-05-23 A. Gerashenko , K. Mikhalev , S. Verkhovskii , T. D'yachkova , A. Tyutyunnik , V. Zubkov

$^{11}$B NMR measurements have been performed in $^{11}$B enriched MgB$_2$ powder samples in external fields of 0.813, 1.55, 4.7 and 7.2 T both in the normal phase and in the superconducting phase. A previously unreported dipolar Pake…

超导电性 · 物理学 2007-05-23 S. H. Baek , B. J. Suh , E. Pavarini , F. Borsa , R. G. Barnes , S. L. Budko , P. C. Canfield

We report a detailed study of $^{11}$B and $^{27}$Al NMR spin-lattice relaxation rates ($1/T_1$), as well as of $^{27}$Al Knight shift (K) of Mg$_{1-x}$Al$_x$B$_2$, $0\leq x\leq 1$. The obtained ($1/T_1T$) and K vs. x plots are in excellent…

超导电性 · 物理学 2016-08-31 G. Papavassiliou , M. Pissas , M. Karayanni , M. Fardis , S. Koutandos , K. Prassides

^25Mg NMR spectra and nuclear spin-lattice relaxation time, T_1, have been measured in polycrystalline ^25MgB_2 with a superconducting transition temperature T_c = 39.0 K in zero magnetic field. From the first order and second order…

超导电性 · 物理学 2009-11-07 M. Mali , J. Roos , A. Shengelaya , H. Keller , K. Conder

Nuclear relaxation in half-integer spin chains at low temperatures (T << J, the antiferromagnetic exchange constant) is dominated by dissipation from a gas of thermally-excited, overdamped, spinons. The universal low temperature dependence…

凝聚态物理 · 物理学 2009-10-22 Subir Sachdev

We investigate the dynamically polarized nuclear-spin system in Fe/\emph{n}-GaAs heterostructures using the response of the electron-spin system to nuclear magnetic resonance (NMR) in lateral spin-valve devices. The hyperfine interaction is…

介观与纳米尺度物理 · 物理学 2019-08-14 Kevin D. Christie , Chad C. Geppert , Sahil J. Patel , Q. O. Hu , Chris J. Palmstrøm , Paul A. Crowell

Nuclear Magnetic Resonance (NMR) is a tool of choice to characterize molecular motions. In biological macromolecules, pico- to nano-second motions, in particular, can be probed by nuclear spin relaxation rates which depend on the time…

化学物理 · 物理学 2022-10-12 Nicolas Bolik-Coulon , Fabien Ferrage

We calculate electron and nuclear spin relaxation rates in a quantum dot due to the combined action of Nyquist noise and electron-nuclei hyperfine or spin-orbit interactions. The relaxation rate is linear in the resistance of the gate…

介观与纳米尺度物理 · 物理学 2007-05-23 Florian Marquardt , Veniamin A. Abalmassov

We propose a probe based on nuclear relaxation and Knight shift measurements for the Kondo scenario for the "0.7 feature" in semiconductor quantum point contact (QPC) devices. We show that the presence of a bound electron in the QPC would…

介观与纳米尺度物理 · 物理学 2008-06-05 V. Tripathi , N. R. Cooper

Nuclear magnetic resonance (NMR) provides local, bulk information about the electronic properties of materials, and it has been influential for theory of high-temperature superconducting cuprates. Importantly, NMR found early that nuclear…

超导电性 · 物理学 2019-03-07 Marija Avramovska , Danica Pavićević , Jürgen Haase

In response to recent nuclear-magnetic-resonance measurements on a ferrimagnetic chain compound NiCu(C_7H_6N_2O_6)(H_2O)_3 2H_2O [Solid State Commun. {\bf 113} (2000) 433], we calculate the nuclear spin-lattice relaxation rate 1/T_1 in…

强关联电子 · 物理学 2009-10-31 Shoji Yamamoto

We present nuclear magnetic resonance (NMR) and nuclear quadrupole resonance (NQR) measurements performed on single crystalline \ccag{}, a member of a recently discovered family of heavy fermion materials Ce$_2M$Al$_7$Ge$_4$ ($M$ = Co, Ir,…

We first analyze the recent experimental data on the nuclear spin-lattice relaxation rate of the Weyl semimetal TaP. We argue that its non-monotonic temperature dependence is explained by the temperature dependent chemical potential of Weyl…

介观与纳米尺度物理 · 物理学 2019-03-07 Z. Okvátovity , H. Yasuoka , M. Baenitz , F. Simon , B. Dóra

This paper proposes an effective diffusion equation method to analyze nuclear magnetic resonance (NMR) relaxation. NMR relaxation is a spin system recovery process, where the evolution of the spin system is affected by the random field due…

化学物理 · 物理学 2021-03-31 Guoxing Lin

NMR line shift and nuclear spin-lattice relaxation rate T_1^{-1} of 11B and 25Mg were measured in superconducting MgB_2 (T_c^{ons}=38K) structurally disordered by nuclear reactor neutrons up to the fluence of thermal neutrons $\Phi=1…

While NMR measurements of nuclear energy spectra are routinely used to characterize the static properties of quantum magnets, the dynamical information locked in NMR 1/T1 relaxation rates remains notoriously difficult to interpret. The…

强关联电子 · 物理学 2011-12-01 Andrew Smerald , Nic Shannon

We report 125Te-NMR studies on a newly discovered heavy fermion superconductor UTe2. Using a single crystal, we have measured the 125Te-NMR Knight shift K and spin-lattice relaxation rate 1/T1 for fields along the three orthorhombic crystal…

‹ 上一页 1 2 3 10 下一页 ›