Compact and Wide Stopband Lowpass Filter Using Open Complementary Split Ring Resonator and Defected Ground Structure

A compact (0.16 λg x 0.08 λg) and wide stop¬band lowpass filter design using open complementary split ring resonator (OCSRR) and defected ground structure (DGS) is presented in this paper. Low pass filter is con-structed using two cascaded stages of OCSRR. Since the rejection bandwidth of the OCSRR is narrow, tapered dumbbell shaped DGS section is placed under the OCSRR to enhance the bandwidth. The cutoff frequency (fc) of the proposed lowpass filter is 1.09 GHz. The rejection band¬width of the filter covers the entire ultra wideband spec¬trum. Hence the spurious passband suppression is achieved up to 10 fc. The designed filter has been fabri¬cated and validated by experimental result

Tensor network annealing algorithm for two-dimensional thermal states

Tensor network methods have become a powerful class of tools to capture strongly correlated matter, but methods to capture the experimentally ubiquitous family of models at finite temperature beyond one spatial dimension are largely lacking. We introduce a tensor network algorithm able to simulate thermal states of two-dimensional quantum lattice systems in the thermodynamic limit. The method develops instances of projected entangled pair states and projected entangled pair operators for this purpose. It is the key feature of this algorithm to resemble the cooling down of the system from an infinite temperature state until it reaches the desired finite-temperature regime. As a benchmark, we study the finite-temperature phase transition of the Ising model on an infinite square lattice, for which we obtain remarkable agreement with the exact solution. We then turn to study the finite-temperature Bose-Hubbard model in the limits of two (hard-core) and three bosonic modes per site. Our technique can be used to support the experimental study of actual effectively two-dimensional materials in the laboratory, as well as to benchmark optical lattice quantum simulators with ultracold atoms

A Compact Dual Band-Notched Circular Ring Printed Monopole Antenna for Super wideband Applications

In this article, a simple and compact dual band-notched (DBN) super wideband (SWB) printed monopole antenna (PMA) has been proposed. The proposed antenna composed of a circular PMA, which is connected through a 50-Ω triangular tapered microstrip fed line (TTMFL) and a round-cornered finite ground plane (RCFGP). It exhibits a very wide frequency band from 1.6–25 GHz (ratio band¬width of 15.63:1) with a voltage standing wave ratio (VSWR) ≤ 2. By employing a U-shaped parasitic element (USPE) near the RCFGP and a T-shaped protruded stub (TSPS) inside the radiating patch, a single band-notched (SBN) characteristic in the frequency band of 3.2–4.4 GHz (WiMAX/C-band) is generated. In order to realize the sec¬ond band-notched function for X-band satellite communication systems (7.2–8.4 GHz), a U-shaped slot (USS) has been inserted in the RCFGP. The overall dimension of the proposed antenna is 24x30x0.787 mm3 and occupies a relatively small space compared to the existing DBN an¬tennas. Good agreement has been attained between pre¬dicted and measured results

The classical two dimensional Heisenberg model revisited An SU 2 symmetric tensor network study

The classical Heisenberg model in two spatial dimensions constitutes one of the most paradigmatic spin models, taking an important role in statistical and condensed matter physics to understand magnetism. Still, despite its paradigmatic character and the widely accepted ban of a continuous spontaneous symmetry breaking, controversies remain whether the model exhibits a phase transition at finite temperature. Importantly, the model can be interpreted as a lattice discretization of the O 3 non linear sigma model in 1 1 dimensions, one of the simplest quantum field theories encompassing crucial features of celebrated higher dimensional ones like quantum chromodynamics in 3 1 dimensions , namely the phenomenon of asymptotic freedom. This should also exclude finite temperature transitions, but lattice effects might play a significant role in correcting the mainstream picture. In this work, we make use of state of the art tensor network approaches, representing the classical partition function in the thermodynamic limit over a large range of temperatures, to comprehensively explore the correlation structure for Gibbs states. By implementing an SU 2 symmetry in our two dimensional tensor network contraction scheme, we are able to handle very large effective bond dimensions of the environment up to amp; 967;effE amp; 8764;1500, a feature that is crucial in detecting phase transitions. With decreasing temperatures, we find a rapidly diverging correlation length, whose behaviour is apparently compatible with the two main contradictory hypotheses known in the literature, namely a finite T transition and asymptotic freedom, though with a slight preference for the secon

Pinwheel valence bond crystal ground state of the spin 1 2 Heisenberg antiferromagnet on the shuriken lattice

We investigate the nature of the ground state of the spin 1 2 Heisenberg antiferromagnet on the shuriken lattice by complementary state of the art numerical techniques, such as variational Monte Carlo VMC with versatile Gutzwiller projected Jastrow wave functions, unconstrained multivariable variational Monte Carlo mVMC , and pseudofermion pseudo Majorana functional renormalization group PFFRG PMFRG methods. We establish the presence of a quantum paramagnetic ground state and investigate its nature, by classifying symmetric and chiral quantum spin liquids, and inspecting their instabilities towards competing valence bond crystal VBC orders. Our VMC analysis reveals that a VBC with a pinwheel structure emerges as the lowest energy variational ground state, and it is obtained as an instability of the U 1 Dirac spin liquid. Analogous conclusions are drawn from mVMC calculations employing accurate BCS pairing states supplemented by symmetry projectors, which confirm the presence of pinwheel VBC order by a thorough analysis of dimer dimer correlation functions. Our work highlights the nontrivial role of quantum fluctuations via the Gutzwiller projector in resolving the subtle interplay between competing order

Assessing learning preferences of dental students using visual, auditory, reading-writing, and kinesthetic questionnaire

Introduction: Educators of the health care profession (teachers) are committed in preparing future health care providers, but are facing many challenges in transmitting their ever expanding knowledge to the students. This study was done to focus on different learning styles among dental students. Aim: To assess different learning preferences among dental students. Materials and Methods: This is a descriptive cross-sectional questionnaire study using visual, auditory, reading-writing, and kinesthetic questionnaire among dental students. Results: Majority 75.8% of the students preferred multimodal learning style. Multimodal learning was common among clinical students. No statistical significant difference of learning styles in relation to gender (P > 0.05). Conclusion: In the present study, majority of students preferred multimodal learning preference. Knowledge about the learning style preference of different profession can help to enhance the teaching method for the students