Correlation of clusters: Partially truncated correlation functions and their decay

In this article, we investigate partially truncated correlation functions (PTCF) of infinite continuous systems of classical point particles with pair interaction. We derive Kirkwood-Salsburg-type equations for the PTCF and write the solutions of these equations as a sum of contributions labelled by certain forests graphs, the connected components of which are tree graphs. We generalize the method introduced by R.A. Minlos and S.K. Poghosyan (1977) in the case of truncated correlations. These solutions make it possible to derive strong cluster properties for PTCF which were obtained earlier for lattice spin systems.Comment: 31 pages, 2 figures. 2nd revision. Misprints corrected and 1 figure adde

Fast and High-Fidelity Entangling Gate through Parametrically Modulated Longitudinal Coupling

We investigate an approach to universal quantum computation based on the modulation of longitudinal qubit-oscillator coupling. We show how to realize a controlled-phase gate by simultaneously modulating the longitudinal coupling of two qubits to a common oscillator mode. In contrast to the more familiar transversal qubit-oscillator coupling, the magnitude of the effective qubit-qubit interaction does not rely on a small perturbative parameter. As a result, this effective interaction strength can be made large, leading to short gate times and high gate fidelities. We moreover show how the gate infidelity can be exponentially suppressed with squeezing and how the entangling gate can be generalized to qubits coupled to separate oscillators. Our proposal can be realized in multiple physical platforms for quantum computing, including superconducting and spin qubits.Comment: 5 pages, 3 figures, Supplemental Materia

Kaleidoscope Wellness | Destigmatizing Mental Health for Teens by Design

Motivation Mental health is a global public health crisis. (Marcus et. al, 2012; WHO, 2020). Although there is a growing acceptance of the complexities surrounding mental illness, care delivery for adolescents with mental health concerns remains highly stigmatized, which contributes to delays in care (Hoisington et. al, 2019; Burns & Birrell, 2014). Half of all mental illnesses can be detected prior to the age of 14 (National Alliance for Mental Health, 2020). While research exploring how the physical health care environment impacts health and well-being for patients has evolved immensely over the past two decades, research on how facility design contributes to healing for adolescents with mental health concerns is lacking. (Hoisington et al, 2019). Problem Historically, adolescents in need of mental health services were often sent away to a mental health facility that was isolated from the community. The design of these facilities reflected a priority to maximize safety and minimize the risk for self-harm, over the need to provide a human-centered and therapeutic environment that facilitates ongoing healing and readjustment into a daily routine upon discharge (Bil, 2016). Seclusion from the community has contributed to a lack of awareness and stigmatizing attitudes toward peers with mental health concerns, amongst adolescents (Raballo et al., 2017; Shepley, 2016; Bil, 2016). The design of mental health facilities for adolescents has not focused on providing a therapeutic milieu that facilitates information sharing and relationship-building between adolescents with mental health concerns, and the peers they prioritize as their support network (Hoisington et. al, 2019). The design precedents found indicate a focus on design strategies for institutional spaces, such as hospitals and clinics, but few, if any, examples exist to provide guidance to designers looking to make spaces that facilitate community-based integrated care interventions for adolescents with mental health concerns (Hoisington, 2019). This is problematic because adolescents often prefer to seek help from peers; as such, there is a need for spaces to facilitate consistent peer-to-peer interaction and support. (Yap et. al, 2013; Hart, 2017). Methods An extensive literature review was conducted to assess the prevalence and efficacy of non-clinical programs taking place within community-integrated spaces, that focus on mental health education for adolescents. Interviews were conducted with an adolescent medicine physician, one licensed clinical social worker, two general pediatricians, and one high school counselor, to better understand the challenges facing adolescents with mental health concerns and the ways in which the built environment can influence healing and recovery during a time of significant biological, social, cognitive developmental changes and transitions. The literature was also reviewed to identify case studies with successful teen-centered interventions that can be replicated to improve awareness and peer-to-peer support. The Whole Building Design Guide for youth centers, and various design guides for designing teen spaces in public libraries were reviewed to better understand adolescents’ perceived needs in the design spaces meant to help them thrive. Results Adolescents are a vulnerable population with unique psychosocial needs (Bluth, 2017). There is a need to normalize conversations around mental illness, to reduce stigmatizing attitudes and improve help-seeking behaviors for adolescents with mental health concerns (Hoisington, 2019, Shepley 2016; Clement et. al, 2015). In addition to understanding the health implications of the design of institutionalized health facilities for all of the users, designers must also consider the influence of the design of spaces thoughtfully embedded within communities, that provide mental health services for adolescents. This is an under-explored issue, and evidence-based design strategies can be used to positively impact the design of spaces where these services are offered (Liddicoat et. al, 2020). The research reveals a lack of spaces with programming focused on mental health education for teens and their peers. Conclusion For this project, a teen mental wellness and creative arts center was designed for adolescents with mental health concerns and their peers. This supportive resource center also aims to provide educational resources for professionals such as teachers, social workers, counselors, and physicians, as well as family members, and for the surrounding community. This space seeks to normalize conversations around mental health, by providing a safe space where evidence based-training is provided, to help increase awareness and facilitate a strong social support network for adolescents, to help improve their quality of life into adulthood. This space strives to change the narrative of how mental illness is perceived by providing an energizing environment and resources to encourage the development of sustained mental wellness habits for all teens and the community at large, whether or not there has been an official diagnosis of mental illness

Refined masses and distance of the young binary Haro 1-14 C

We aim to refine the dynamical masses of the individual component of the low-mass pre-main sequence binary Haro 1-14 C. We combine the data of the preliminary orbit presented previously with new interferometric observations obtained with the four 8m telescopes of the Very Large Telescope Interferometer. The derived masses are M_a=0.905\pm0.043\,\Msun and M_b=0.308\pm0.011\,\Msun for the primary and secondary components, respectively. This is about five times better than the uncertainties of the preliminary orbit. Moreover, the possibility of larger masses is now securely discarded. The new dynamical distance, $d=96\pm\,9\,$pc, is smaller than the distance to the Ophiuchus core with a significance of $2.6\,\sigma$. Fitting the spectral energy distribution yields apparent diameters of \phi_a=0.13\pm0.01\mas and \phi_b=0.10\pm0.01\mas (corresponding to \Ra=1.50\,\Rsun and \Rb=1.13\,\Rsun) and a visual extinction of $A_v\approx1.75$. Although the revised orbit has a nearly edge-on geometry, the system is unlikely to be a long-period eclipsing binary. The secondary in Haro~1-14C is one of the few low-mass, pre-main sequence stars with an accurately determined dynamical mass and distance

Collective resonances in gold nanoparticle arrays

Baptiste Auguié and William L. Barnes, Physical Review Letters, Vol. 101, article 143902 (2008). Copyright © 2008 by the American Physical Society.We present experimental evidence of sharp spectral features in the optical response of 2D arrays of gold nanorods. A simple coupled dipole model is used to describe the main features of the observed spectral line shape. The resonance involves an interplay between the excitation of plasmons localized on the particles and diffraction resulting from the scattering by the periodic arrangement of these particles. We investigate this interplay by varying the particle size, aspect ratio, and interparticle spacing, and observe the effect on the position, width, and intensity of the sharp spectral feature