We have measured the heat capacity of an optically trapped, strongly interacting Fermi gas atoms. A precise addition energy to is followed by single-parameter thermometry, which determines empirical temperature parameter cloud. Our measurements reveal a clear transition in capacity. The and spatial profile are computed using theory crossover from Bose superfluids at finite temperatures. calibrates parameter, yields excellent agreement with data, predicts onset superfluidity observed point.

The theory of unconventional superconductors continues to provide profound puzzles. crossover between the weakly coupled Bardeen-Cooper-Schrieffer (BCS) state and strong-pairing Bose-Einstein condensate (BEC) provides a useful perspective on how address these questions. This paper describes self-consistent framework for thinking about regime in two limits. review discusses what extent this BCS-BEC applies range classes superconducting materials including cuprates, iron pnictides, twisted...

We propose a theoretical description of the superconducting state under- to overdoped cuprates, based on short coherence length these materials and associated strong pairing fluctuations. The calculated ${T}_{c}$ zero temperature excitation gap $\ensuremath{\Delta}(0)$, as function hole concentration $x$, are in semiquantitative agreement with experiment. Although ${T}_{c}/\ensuremath{\Delta}(0)$ has non-BCS $x$ dependence, $\ensuremath{\Delta}(T)$ deviates significantly from BCS prediction,...

The integration of Global Positioning System (GPS) real-time kinematics (RTK) and an inertial navigation system (INS) has been widely used in many applications, such as mobile mapping autonomous vehicle control. Such applications require high-accuracy position information. However, continuous reliable positioning is still challenging for GPS/INS urban environments because the limited satellite visibility, increasing multipath, frequent signal blockages. Recently, with rapid deployment...

Accurate measurement of the railway track geometry is a task fundamental importance to ensure quality in both construction phase and regular maintenance stage. Conventional measuring trolleys (TGMTs) combination with classical geodetic surveying apparatus such as total stations alone cannot meet requirements accuracy efficiency at same time. fast applications call for an innovative method that can measure all or most geometric parameters short time without interrupting traffic. We provide...

We study the superfluid state of atomic Fermi gases using a BCS-Bose-Einstein-condensation crossover theory. Our approach emphasizes noncondensed fermion pairs which strongly hybridize with their (Feshbach-induced) molecular boson counterparts. These lead to pseudogap effects above ${T}_{c}$ and non-BCS characteristics below. discuss how these influence experimental signatures superfluidity.

We address recent momentum resolved radio frequency (RF) experiments on ultracold trapped Fermi gases of $^{40}$K. show that RF probes provide measurements the centrally important fermionic spectral function. They also serve to remove ambiguity plaguing interpretation integrated by establishing a clear dispersion signature pairing. find temperature dependence function is dramatic at unitarity, and, importantly, smooth from above below $T_c$ throughout BCS-BEC crossover. This should be tested...

Oriented diamond films were achieved on Si(001) and Si(111) substrates via hot filament chemical vapor deposition (HFCVD) with the orientation relationship of dia〈110〉//Si〈110〉 dia(001)//Si(001) for Si(001), dia〈11̄0〉//Si〈11̄0〉 dia(111)//Si(111) Si(111). The negatively biased relative to during nucleation stage. as-grown characterized by scanning electron microscopy (SEM) Raman spectroscopy. role negative bias is discussed in light differences between HFCVD microwave plasma CVD. In...

We investigate the behavior of superconducting transition temperature within a previously developed BCS Bose-Einstein crossover picture. This picture, based on decoupling scheme Kadanoff and Martin, further extended by Patton, can be used to derive simple form for in presence pseudogap. extend previous work which addressed case s-wave pairing jellium, explore solutions ${T}_{c}$ as function variable coupling more physically relevant situations. thereby ascertain effects reduced...

We derive the underlying finite temperature theory which describes Fermi gas superfluidity with population imbalance in a homogeneous system. compute pair formation and superfluid transition $T_c$ density manner consistent standard ground state equations, thereby present complete phase diagram. Finite stabilizes superfluidity, as manifested by two solutions for $T_c$, or low $T$ instabilities. At unitarity polarized is an ``intermediate superfluid".

Odometer and nonholonomic constraints are crucial external aids for inertial navigation systems (INSs) to achieve desirable positioning accuracy pipeline inspection gauges (PIGs). Exploiting the maximum potential of these requires accurate knowledge inevitably existing misalignment in attitudes measurement unit (IMU) with respect host vehicle (i.e., IMU mounting angle relative PIG). In this paper, we address calibration a PIG without using sophisticated equipment. Instead, proposed method...

We study quantum geometric contributions to the Berezinskii-Kosterlitz-Thouless (BKT) transition temperature, $T_{\mathrm{BKT}}$, in presence of fluctuations beyond BCS theory. Because effects become progressively more important with stronger pairing attraction, a full understanding 2D multi-orbital superconductivity requires incorporation preformed pairs. find it is through effective mass these pairs that geometry enters theory and this suggests are present non-superconducting pseudogap...

In this paper we study the BCS Bose-Einstein condensation (BEC) crossover scenario within superconducting state, using a T-matrix approach which yields ground state proposed by Leggett. Here extend analysis to finite temperatures T and interpret resulting physics. We find two types of bosoniclike excitations system: long lived, incoherent pair collective modes order parameter, have different dynamics. Using gauge invariant formalism, addresses their contrasting behavior as function coupling...

The existence of a normal state spectral gap in underdoped cuprates raises important questions about the associated superconducting phase. For example, how does this pseudogap evolve into its below Tc counterpart? In paper we characterize unusual superconductor by investigating nature ``residual'' and, find that it leads to an distinction between excitation and order parameter. Our approach is based on conserving diagrammatic BCS Bose-Einstein crossover theory which yields precise result...

We calculate the entropy in a trapped, resonantly interacting Fermi gas as function of temperature for wide range magnetic fields between BCS and Bose-Einstein condensation endpoints. This provides basis important technique adiabatic sweep thermometry, serves to characterize quantitatively evolution nature excitations gas. The results are then used calibrate several ground breaking experiments on $^6$Li $^{40}$K.

We present phase diagrams for population-imbalanced, trapped Fermi superfluids near unitarity. In addition to providing quantitative values the superfluid transition temperature, pairing onset and line (separating Sarma separation regimes), we study experimental signatures of these transitions based on density profiles differences at center. Predictions BCS side resonance show unexpected behavior, which should be searched experimentally.

In this paper we present an overview of radio frequency (RF) spectroscopy in the atomic Fermi superfluids.An ultimate goal is to suggest new directions cold gas research agenda from condensed matter perspective.Our focus on experimental and theoretical literature gases photoemission cuprates particularly as it pertains areas overlap.In addition a comparison with cuprates, contains systematic theory RF spectroscopy, both momentum integrated resolved.It should be noted that resolved forms are...

High-rate GNSS positioning has been widely investigated and applied in science engineering. We extend it to high-rate attitude determination under a multi-GNSS constellation. A series of experiments conducted on platform with three 50 Hz geodetic receivers two high-grade inertial measurement units (IMU). The solutions are computed for each the systems combined constellation by either using short baselines correct ambiguity resolution or precise point (PPP) compared IMU measurements. In case...

Abstract Superconductivity in crystals without inversion symmetry has received extensive attention due to its unconventional pairing and possible nontrivial topological properties. Using first-principles calculations, we systemically study the electronic structure of noncentrosymmetric superconductors A 2 Cr 3 As (A = Na, K, Rb, Cs). Topologically protected triply degenerate points connected by one-dimensional arcs appear along C axis, coexisting with strong ferromagnetic (FM) fluctuations...