In traditional Hanbury Brown and Twiss (HBT) schemes, the thermal intensity-intensity correlations are phase insensitive. Here we propose a modified HBT scheme with phase conjugation to demonstrate the phase-sensitive and nonfactorizable features for
thermal intensity-intensity correlation speckle. Our scheme leads to results that are similar to those of the two-photon speckle. We discuss the possibility of the experimental realization. The results provide us a deeper insight of the thermal correlations and may lead to more significant applications in imaging and speckle technologies.
We investigate the Goos-H{a}nchen (GH) shifts of partially coherent fields (PCFs) by using the theory of coherence. We derive a formal expression for the GH shifts of PCFs in terms of Mercers expansion, and then clearly demonstrate the dependence of
the GH shift of each mode of PCFs on spatial coherence and beam width. We discuss the effect of spatial coherence on the resultant GH shifts, especially for the cases near the critical angles, such as totally reflection angle.
This comment is to show that our simulation data, based on our theory and method in Ref. [J. Phys. B 41, 055401 (2008)], are also in agreement with the experimental data presented for $D_{p}-D_{s}$ in Ref. [Phys. Rev. Lett. textbf{109}, 213901 (2012)
]. We also demonstrate how to show the effect of spatial coherence on the GH shifts in this comment, therefore we disagree with the claims in Ref. [Phys. Rev. Lett. textbf{109}, 213901 (2012)].
It is shown that the spatial Goos-Hanchen shift is greatly affected by spatial coherence. A typical example is given.
We have theoretically investigated the properties of electronic transport in graphene heterostructures, which are consisted of two different graphene superlattices with one-dimensional periodic potentials. It is found that such heterostructures posse
ss an unusual tunneling state occurring inside the original forbidden gaps, and the electronic conductance is greatly enhanced and Fano factor is strongly suppressed near the energy of the tunneling state. Finally we present the matching condition of the impedance of the pseudospin wave for occuring the tunneling state by using the Bloch-wave expansion method.
In terms of operator, the two complementary quantities, the predictability and visibility, are reinvestigated in a two-way interferometer. One Hermitian operator and one non-Hermitian operator (composed of two Hermitian operators) are introduced for
the predictability and visibility, respectively. The predictability and visibility can not be measured exactly simultaneously, due to the non-commutation between the two operators. The sum of the variances of the predictability and visibility (the total variance), is used to measure the uncertainty, which is linked to the complementarity relation through the equation, $(delta_P)^2+(delta_Vf)^2+P^2+V^2=2$ . This new description for the predictability and visibility connects the complementarity and the uncertainty relations, although neither of them can be derived directly from the other.
In this paper, the electronic band structures and its transport properties in the gapped graphene superlattices, with one-dimensional (1D) periodic potentials of square barriers, are systematically investigated. It is found that a zero averaged wave-
number (zero-$overline{k}$ ) gap is formed inside the gapped graphene-based superlattices, and the condition for obtaining such a zero-$overline{k}$ gap is analytically presented. The properties of this zero-$overline{k}$ gap including its transmission, conductance and Fano factor are studied in detail. Finally it is revealed that the properties of the electronic transmission, conductance and Fano factor near the zero-$overline{k}$ gap are very insensitive to the structural disorder for the finite graphene-based periodic-barrier systems.
The Dirac point with a double-cone structure for optical fields, an optical analogy Dirac fermions in graphene, can be realized in optically homogenous metamaterials. The condition for the realization of Dirac point in optical systems is the varying
of refractive index from negative to zero and then to positive. Our analytical and numerical analysis have verified that, similar to electrons in graphene, the light field near the Dirac point possesses of the pseudodiffusive property, obeying the 1/L scaling law, where L is the propagating distance of light inside the media.
We present a model for a vacuum-like effective medium composed of the absorbing and gain media under the special designed parameters. Within the linear response theory, we prove that any pulse signal (with or without a discontinuity) through such a k
ind of vacuum-like effective media is always equal to the light speed in vacuum () without any distortion. As well known that the group velocity in anomalous or normal dispersive media may be smaller or larger than, or even become negative, but the discontinuous point always propagates at the velocity . Therefore we present some discussions on different definitions of the signals, based on the light pulses with a well-defined shape or with a sudden change, for trying to understand two possibilities for the signal velocity without violating the causality.
We show that the essential physics of the Hanbury Brown-Twiss (HBT) and the thermal light ghost imaging experiments is the same, i.e., due to the intensity fluctuations of the thermal light. However, in the ghost imaging experiments, a large number o
f bits information needs to be treated together, whereas in the HBT there is only one bit information required to be obtained. In the HBT experiment far field is used for the purpose of easy detection, while in the ghost image experiment near (or not-far) field is used for good quality image.
