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News On Nanomaterials

In these days, the Journal of RSC advances published a new paper entitled as “Organic and inorganic nanomaterials: fabrication, properties and applications”

Nanomaterials and nanoparticles are a burgeoning field of research and a rapidly expanding technology sector in a wide variety of application domains. Nanomaterials have made exponential progress due to their numerous uses in a variety of fields, particularly the advancement of engineering technology. Nanoparticles are divided into various groups based on the size, shape, and structural morphology of their bodies. The 21st century’s defining feature of nanoparticles is their application in the design and production of semiconductor devices made of metals, metal oxides, carbon allotropes, and chalcogenides. For the researchers, these materials then opened a new door to a variety of applications, including energy storage, catalysis, and biosensors, as well as devices for conversion and medicinal uses. For chemical and thermal applications, ZnO is one of the most stable n-type semiconducting materials available. It is utilized in a wide range of products, from luminous materials to batteries, supercapacitors, solar cells to biomedical photocatalysis sensors, and it may be found in a number of forms, including pellets, nanoparticles, bulk crystals, and thin films. The distinctive physiochemical characteristics of semiconducting metal oxides are particularly responsible for this. ZnO nanostructures differ depending on the synthesis conditions, growth method, growth process, and substrate type. A number of distinct growth strategies for ZnO nanostructures, including chemical, physical, and biological methods, have been recorded. These nanostructures may be synthesized very simply at very low temperatures. This review focuses on and summarizes recent achievements in fabricating semiconductor devices based on nanostructured materials as 2D materials as well as rapidly developing hybrid structures. Apart from this, challenges and promising prospects in this research field are also discussed.

Congratulations for Our New Paper in Journal of Optik

Plasmonic heterostructure biosensor based on perovskite/two dimensional materials

Seyedeh Bita Saadatmand, Samad Shokouhi, Seyedeh Mehri Hamidi,
Hamidreza Ahmadi, Maryam Babaei

We propose a bimetallic glucose sensor based on surface plasmon using three-dimensional metal halide perovskites and two-dimensional material. The transfer matrix method and density functional theory corroborated by finite-element simulation are used for numerical analysis for the first time. In the angle interrogation method, MAPbBr3 and monolayer graphene enhanced sensitivity by 254%. A conventional Ag-based sensor has a sensitivity of 113 deg/RIU, whereas the bimetallic/ MAPbBr3/ graphene stack has a sensitivity of 400.25 deg/RIU with 22 nm Ag/ 22 nm Au/ 17 nm MAPbBr3/ graphene. Furthermore, the signal-to-noise ratio, figure of merit, and detection range of the proposed structure are 0.153 deg􀀀 1, 61.23 RIU􀀀 1, and 1.33–1.345, respectively. We also investigate the ductility, temperature stability, thermodynamics, and mechanical stability of metal halide perovskites in detail. The results show that compared to published results, the proposed SPR sensor has significantly improved characteristics.

News On Atomic Spectroscopy

In these days, the Journal of SSRN 4572475 published a new paper entitled as “Frequency Stabilization Technology of 1560-Nm Fiber Faser Based on Rubidium Modulation Transfer Spectroscopy

Abstract: The modulation transfer spectroscopy technique used to stabilize two different transition lines of rubidium, required for laser cooling of atoms, is investigated. The 1560-nm fiber laser is adopted as the laser source, to address the weak spectral features of repumping laser, a theoretical study is conducted followed by experimental verification. The 87Rb D2 line F=1 → F’ = 0,1 cross-transition (close to F = 1 → F’= 2 repumping transition) temperature- enhanced MTS signal is observed. The laser linewidth after locking is 35.36 kHz, and the 1-s stabilities of the frequency stabilized cooling laser and repumping laser are 7.13E-12 and 3.48E-11, respectively.

News On Neuro-Plasmonics

In these days, the journal of Advanced Materials published a new paper entitled as “Toward Plasmonic Neural Probes: SERS Detection of Neurotransmitters through Gold-Nanoislands-Decorated Tapered Optical Fibers with Sub-10 nm Gaps”

Integration of plasmonic nanostructures with fiber-optics-based neural probes enables label-free detection of molecular fingerprints via surface-enhanced Raman spectroscopy (SERS), and it represents a fascinating
technological horizon to investigate brain function. However, developing neu-roplasmonic probes that can interface with deep brain regions with minimal invasiveness while providing the sensitivity to detect biomolecular signatures in a physiological environment is challenging, in particular because the same waveguide must be employed for both delivering excitation light and collecting the resulting scattered photons. Here, a SERS-active neural probe based on a tapered optical fiber (TF) decorated with gold nanoislands (NIs) that can detect neurotransmitters down to the micromolar range is presented. To do this, a novel, nonplanar repeated dewetting technique to fabricate gold NIs with sub-10 nm gaps, uniformly distributed on the wide (square milimeter scale in surface area), highly curved surface of TF is developed. It is experimentally and numerically shown that the amplified broadband near-field enhancement of the high-density NIs layer allows for achieving a limit of detection in aqueous solution of 10−7 m for rhodamine 6G and 10−5 m for sero-tonin and dopamine through SERS at near-infrared wavelengths. The NIs-TF technology is envisioned as a first step toward the unexplored frontier of in vivo label-free plasmonic neural interfaces.

News On Optical Atomic Clock

In these days, the Journal of Physical Review Letters published a new paper entitled as “Improved Limits on the Coupling of Ultralight Bosonic Dark Matter to Photons from Optical Atomic Clock Comparisons

We present improved constraints on the coupling of ultralight bosonic dark matter to photons based on long-term measurements of two optical frequency ratios. In these optical clock comparisons, we relate the frequency of the 2S1=2ðF ¼ 0Þ ↔ 2F7=2 ðF ¼ 3Þ electric-octupole (E3) transition in 171Ybþ to that of the 2S1=2 ðF ¼ 0Þ ↔ 2D3=2 ðF ¼ 2Þ electric-quadrupole (E2) transition of the same ion, and to that of the 1S0 ↔ 3P0 transition in 87Sr. Measurements of the first frequency ratio νE3=νE2 are performed via interleaved interrogation of both transitions in a single ion. The comparison of the single-ion clock based on the E3 transition with a strontium optical lattice clock yields the second frequency ratio νE3=νSr. By constraining oscillations of the fine-structure constant α with these measurement results, we improve existing bounds on the scalar coupling de of ultralight dark matter to photons for dark matter masses in the range of about ð10−24–10−17Þ eV=c2. These results constitute an improvement by more than an order of magnitude over previous investigations for most of this range. We also use the repeated measurements of νE3=νE2 to improve existing limits on a linear temporal drift of α and its coupling to gravity.

News on Plasmonic

In these days, the journal of small science published a new paper entitled as “Switching on Versatility: Recent Advances in Switchable Plasmonic Nanostructures”

Plasmonic nanostructures are emerging as a promising avenue for nanophotonics due to their extreme light and thermal confinement, ultrafast manipulation processes, and potential uses in device miniaturization. However, their fixed functions have limited their versatility in applications. This review provides an overview of recent switchable plasmonic nanostructure engineering techniques, focusing on methods that provide reversible switchability. Passive optical switching, active structure-tunable switching, active material-based switching, and advanced applications, such as multifunctional biomedical sensing, energy harvesting, and dynamic optical devices, are discussed. The specific methods and techniques used to engineer switchable plasmonic nanostructures are also highlighted. By understanding the latest developments and overall trends, this review is expected to help researchers design and fabricate advanced plasmonic nanostructures with unprecedented switch ability and versatility for various applications.

News On Atomic Clock

In these days, the Journal of Applied Physics published a new paper entitled as “An additive-manufactured microwave cavity for a compact cold-atom clock”

ABSTRACT- We present an additive-manufactured microwave cavity for a Ramsey-type, double resonance, compact cold-atom clock. Atoms can be laser cooled inside the cavity using a grating magneto-optic trap with the cavity providing an excellent TE011-like mode while maintaining sufficient optical access for atomic detection. The cavity features a low Q-factor of 360 which conveniently reduces the cavity pulling of the future clock. Despite the potential porosity of the additive-manufacturing process, we demonstrate that the cavity is well-suited for vacuum.
A preliminary clock setup using cold atoms allows for measuring the Zeeman spectrum and Rabi oscillations in the cavity which enables us to infer excellent field uniformity and homogeneity, respectively, across the volume accessed by the cold atoms. Ramsey spectroscopy is demonstrated, indicating that the cavity is suitable for clock applications. Finally, we discuss the limitations of the future clock.

News On Photoacoustic Imaging

In these days, the Journal of Nano Convergence published a new paper entitled as “Functional photoacoustic imaging: from nano‑ and micro‑ to macro‑scale”

Byullee Park, Donghyeon Oh, Jeesu Kim, and Chulhong Kim

Functional photoacoustic imaging is a promising biological imaging technique that offers such unique benefits as scalable resolution and imaging depth, as well as the ability to provide functional information. At nanoscale, photoacoustic imaging has provided super-resolution images of the surface light absorption characteristics of materials and of single organelles in cells. At the microscopic and macroscopic scales. photoacoustic imaging techniques have precisely measured and quantified various physiological parameters, such as oxygen saturation, vessel morphology, blood flow, and the metabolic rate of oxygen, in both human and animal subjects. This comprehensive review provides an overview of functional photoacoustic imaging across multiple scales, from nano to macro, and highlights recent advances in technology developments and applications. Finally, the review surveys the future prospects of functional photoacoustic imaging in the biomedical field.