ترغب بنشر مسار تعليمي؟ اضغط هنا

Search for exotic short-range interactions using paramagnetic insulators

209   0   0.0 ( 0 )
 نشر من قبل Joshua C. Long
 تاريخ النشر 2015
  مجال البحث فيزياء
والبحث باللغة English




اسأل ChatGPT حول البحث

We describe a proposed experimental search for exotic spin-coupled interactions using a solid-state paramagnetic insulator. The experiment is sensitive to the net magnetization induced by the exotic interaction between the unpaired insulator electrons with a dense, non-magnetic mass in close proximity. An existing experiment has been used to set limits on the electric dipole moment of the electron by probing the magnetization induced in a cryogenic gadolinium gallium garnet sample on application of a strong electric field. With suitable additions, including a movable source mass, this experiment can be used to explore monopole-dipole forces on polarized electrons with unique or unprecedented sensitivity. The solid-state, non-magnetic construction, combined with the low-noise conditions and extremely sensitive magnetometry available at cryogenic temperatures could lead to a sensitivity over ten orders of magnitude greater than exiting limits in the range below 1 mm.



قيم البحث

اقرأ أيضاً

We demonstrate that electron electric dipole moment experiments with molecules in paramagnetic state are sensitive to $P,T$-violating nuclear forces and other $CP$-violating parameters in the hadronic sector. These experiments, in particular, measure the coupling constant $C_{SP}$ of the $CP$-odd contact semileptonic interaction. We establish relations between $C_{SP}$ and different $CP$-violating hadronic parameters including strength constants of the $CP$-odd nuclear potentials, $CP$-odd pion-nucleon interactions, quark-chromo EDM and QCD vacuum angle. These relations allow us to find limits on various $CP$-odd hadronic parameters.
We investigate the sensitivities of searches for exotic spin-dependent interactions between the polarized nuclear spins of $^3$He and the particles of unpolarized or polarized solid-state masses using the frequency method and the resonance method. In the frequency method, the spin-dependent interactions act as an effective static magnetic field, causing the frequency shift to the spin precession of $^{3}$He. In the resonance method, proposed by Arvanitaki and Geraci [Phys. Rev. Lett. 113, 161801 (2014)] for the significant improvement of the experimental sensitivities on the spin-dependent interactions, the mass movement is modulated at the Larmor frequency of $^3$He. This results in the modulating spin-dependent interactions inducing an effective oscillatory magnetic field, which can tilt the $^3$He spins, similarly as an oscillatory magnetic field in nuclear magnetic resonance. We estimate the sensitivities of the searches using a room-temperature $^3$He target for its extremely long relaxation time. New limits on the coupling strengths of the spin-dependent interactions can be set in the interaction length range below $10^{-1}$ m.
The available data on neutron scattering were analyzed to constrain a hypothetical new short-range interaction. We show that these constraints are several orders of magnitude better than those usually cited in the range between 1 pm and 5 nm. This di stance range occupies an intermediate space between collider searches for strongly coupled heavy bosons and searches for new weak macroscopic forces. We emphasise the reliability of the neutron constraints in so far as they provide several independent strategies. We have identified the most promising way to improve them.
We have searched for exotic neutrino-electron interactions that could be produced by a neutrino millicharge, by a neutrino magnetic moment, or by dark photons using solar neutrinos in the XMASS-I liquid xenon detector. We observed no significant sign als in 711 days of data. We obtain an upper limit for neutrino millicharge of 5.4$times$10$^{-12} e$ at 90% confidence level assuming all three species of neutrino have common millicharge. We also set flavor dependent limits assuming the respective neutrino flavor is the only one carrying a millicharge, $7.3 times 10^{-12} e$ for $ u_e$, $1.1 times 10^{-11} e$ for $ u_{mu}$, and $1.1 times 10^{-11} e$ for $ u_{tau}$. These limits are the most stringent yet obtained from direct measurements. We also obtain an upper limit for the neutrino magnetic moment of 1.8$times$10$^{-10}$ Bohr magnetons. In addition, we obtain upper limits for the coupling constant of dark photons in the $U(1)_{B-L}$ model of 1.3$times$10$^{-6}$ if the dark photon mass is 1$times 10^{-3}$ MeV$/c^{2}$, and 8.8$times$10$^{-5}$ if it is 10 MeV$/c^{2}$.
56 - Shaoyu Yin , Nigel R. Cooper , 2018
Despite the success in describing a range of quantum many-body states using tensor networks, there is a no-go theorem that rules out strictly local tensor networks as topologically nontrivial groundstates of gapped parent Hamiltonians with short-rang e (including exponentially decaying) couplings. In this work, we show that for free fermions, strictly local tensor networks may describe nonzero temperature averages with respect to gapped Hamiltonians with exponentially decaying couplings. Parent Hamiltonians in this sense may be constructed for any dimensionality and without any obstructions due to their topology. Conversely, we also show that thermal averages with respect to gapped, strictly short-range free-fermion Hamiltonians can be calculated by tensor networks whose links decay exponentially with distance. We also describe a truncation-reconstruction scheme for such tensor networks that leads to a controlled approximation of exact averages in terms of a sequence of related thermal averages. We illustrate our scheme on the two-dimensional Haldane honeycomb model considering both topological and nontopological phases.
التعليقات
جاري جلب التعليقات جاري جلب التعليقات
سجل دخول لتتمكن من متابعة معايير البحث التي قمت باختيارها
mircosoft-partner

هل ترغب بارسال اشعارات عن اخر التحديثات في شمرا-اكاديميا