Proton stability in grand unified theories, in strings and in branes

The conclusions of the Physics Working Group of the International Scoping Study of a future Neutrino Factory and super-beam facility (the ISS) are presented. The ISS was carried out by the international community between NuFact05, (the 7th International Workshop on Neutrino Factories and Super-beams, Laboratori Nazionali di Frascati, Rome, 21–26 June 2005) and NuFact06 (Ivine, CA, 24–30 August 2006). The physics case for an extensive experimental programme to understand the properties of the neutrino is presented and the role of high-precision measurements of neutrino oscillations within this programme is discussed in detail. The performance of second-generation super-beam experiments, beta-beam facilities and the Neutrino Factory are evaluated and a quantitative comparison of the discovery potential of the three classes of facility is presented. High-precision studies of the properties of the muon are complementary to the study of neutrino oscillations. The Neutrino Factory has the potential to provide extremely intense muon beams and the physics potential of such beams is discussed in the final section of the report.

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Physics at a future Neutrino Factory and super-beam facility

We analyze the constraints placed on individual CP-violating phases in the minimal supersymmetric extension of the Standard Model (MSSM) by current experimental bounds on the electric dipole moments (EDMs) of the neutron, Thallium, and Mercury atoms. We identify the four CP-violating phases that are individually highly constrained by current EDM bounds, and we explore how these phases and correlations among them are constrained by current EDM limits. We also analyze the prospective implications of the next generation of EDM experiments. We point out that all other CP-violating phases in the MSSM are not nearly as tightly constrained by limits on the size of EDMs. We emphasize that a rich set of phenomenological consequences is potentially associated with these generically large EDM-allowed phases, ranging from B physics, electroweak baryogenesis, and signals of CP-violation at the CERN Large Hadron Collider and at future linear colliders. Our numerical study takes into account the complete set of contributions from one-and two-loop EDMs of the electron and quarks, one-and two-loop Chromo-EDMs of quarks, the Weinberg 3-gluon operator, and dominant 4-fermion CP-odd operator contributions, including contributions which are both included and not included yet in the CPsuperH2.0 package. We also introduce an open-source numerical package, 2LEDM, which provides the complete set of two-loop electroweak diagrams contributing to the electric dipole moments of leptons and quarks.

https://link.springer.com/content/pdf/10.1007%2FJHEP08%282010%29062.pdf

A comprehensive analysis of electric dipole moment constraints on CP-violating phases in the MSSM

Nuclear magnetic resonance (NMR) signals are detected in microtesla fields. Prepolarization in millitesla fields is followed by detection with an untuned dc superconducting quantum interference device (SQUID) magnetometer. Because the sensitivity of the SQUID is frequency independent, both signal-to-noise ratio (SNR) and spectral resolution are enhanced by detecting the NMR signal in extremely low magnetic fields, where the NMR lines become very narrow even for grossly inhomogeneous measurement fields. MRI in ultralow magnetic field is based on the NMR at ultralow fields. Gradient magnetic fields are applied, and images are constructed from the detected NMR signals.

Squid detected nmr and mri at ultralow fields

As Moore's law is gradually losing its effectiveness, the development of alternative high-speed and low-energy–consuming information technology with postsilicon-advanced materials is urgently needed. The successful application of tunneling magnetoresistance (TMR) in magnetic tunnel junctions (MTJs) has given rise to a tremendous economic impact on magnetic informatics, including magnetoresistive random access memory (MRAM), radiofrequency sensors, microwave generators, and neuromorphic computing networks. The emergence of two-dimensional (2D) materials brings opportunities for MTJs based on 2D materials, which have many attractive characteristics and advantages. In particular, the recently discovered intrinsic 2D ferromagnetic materials with high spin polarization hold the promise for next-generation nanoscale MTJs. Various 2D materials, such as semimetallic graphene, insulating h-BN, semiconducting MoS2, magnetic semiconducting CrI3, magnetic metallic Fe3GeTe2, and some other recently emerged 2D materials, are discussed as the electrodes and/or central scattering materials of MTJs in this review. We discuss the fundamental and main issues facing MTJs; review the current progress made with 2D MTJs; briefly comment on work with some specific 2D materials and highlight how they address the current challenges in MTJs; and, finally, offer an outlook and perspective of 2D MTJs.

Recent progress and challenges in magnetic tunnel junctions with 2D materials for spintronic applications

https://physicstoday.scitation.org/doi/pdf/10.1063/1.2405630

Philip F. Schewe

Papers

A new limit on the permanent electric

The massive Northeast blackout

A single-spin transistor

Large, mature galaxies formed

A liquid-gas phase transition for nuclei