Osm Physics by Ashish

  Thermal evaporation is a common Physical Vapor Deposition (PVD) technique used to create thin films of material on a substrate . The process involves heating a solid source material within a high-vacuum chamber until it vaporizes; these vaporized atoms or molecules then travel in a straight line to a cooler substrate, where they condense to form a thin, uniform coating.  Core Mechanism The process relies on three critical components to ensure high-quality film deposition:  High Vacuum Environment: Typically conducted at pressures below 10^{-5}Torr. This provides a "mean free path"—the average distance a particle travels before colliding with another—that is longer than the distance between the source and the substrate, ensuring atoms arrive unscattered. Heating Source: The material is heated until its vapor pressure becomes significant. Condensation: The vapor reaches the substrate (e.g., a silicon wafer or glass slide) and transitions back into a solid state, buil...

 Nanostructured materials (with dimensions typically in the 1–100 nm range) can be synthesized using a wide variety of physical and chemical methods . Each approach differs in terms of cost, scalability, control over size/shape, and application suitability. 1. Physical Methods of Nanostructured Materials Physical methods generally involve top-down approaches , where bulk materials are broken down into nanoscale structures. (a) Mechanical Milling (Ball Milling) Bulk material is ground into nanoparticles using high-energy balls. Advantages: Simple, cost-effective, scalable. Disadvantages: Contamination, poor control over shape and size. (b) Physical Vapor Deposition (PVD) Material is vaporized and deposited on a substrate in vacuum. Techniques include: Thermal evaporation Sputtering Applications: Thin films, coatings, electronics. (c) Laser Ablation High-energy laser pulses strike a target material to produce nanoparticles. Advantages: High purity, no chemical contamination. Dis...

-Spectroscopy Lab  To study the diffraction pattern of LASER light using single slit.  Verification of Cauchy's Dispersion relation.  Determine the Planck constant using a solar Cell.  Determination of the velocity of Ultrasonic waves.  To determine the wavelength of He-Ne Laser.  To find the Bohr Magneton by Zeeman Effect Experiment.

 . Nanotechnology-II Unit-I Nanoscale Properties–I: Magnetism: Magnetic Moment in clustersor Nanoparticles, Magnetic Order, coercivity, Magnetocrystalline Anisotropy, thermal activation and Superparamagneticeffects. Electronics and Optoelectronics: Ǫuantum Confinement of Super lattices and Ǫuantum Wells, Doping of a Nanoparticle, Excitonic Binding and Recombination Energies, Capacitance in a Nanoparticle. Unit-II Nanoscale properties – Il: Diffusion in Nanocrystalline Materials: Diffusion In Grain Boundaries Of Metals, Nanocrystalline Ceramics, Correlation Between Diffusion and Crystallite Growth, Other properties: brief overview of optical properties, mechanical properties including superplasticity phenomena, reactivity of nanoparticles. Unit-III Characterization Methods: X-ray diffraction: Debye-Scherer formula, dislocation density, micro strain. Synchrotron Radiation: Principle and Applications. Dynamic Light Scattering (DLS), Electron microscopes: Scanning Electron Microscope (...

 Syllabus :  Generic Methodologies for Nanotechnology: Introduction and classification, What is nanotechnology? Classification of nanostructures: Nanoscale architecture; The free electron model and energy bands, Crystalline solids, Periodicity of crystal lattices, Electronic conduction ; Effects of the nanometer length scale , Changes to the system total energy, Changes to the system structure , How nanoscale dimensions affect properties. 1. Introduction to Nanotechnology Nanotechnology is the branch of science and engineering that deals with the study, design, synthesis, characterization, and application of materials and devices at the nanometer scale . The word nano is derived from the Greek word nanos , meaning dwarf . In measurement, 1 nanometer (nm) = 10⁻⁹ meters Nanotechnology focuses on materials whose size ranges from 1 nm to 100 nm . At this scale, materials exhibit unique physical, chemical, electrical, mechanical, and optical properties that differ significantly ...

. B.Sc. VI Semester (Physics Lab) 1.       Determination of Planck's constant by photo cell (retarding potential method using optical filters, preferably five wavelengths). 2.       Determination of Planck's constant using solar cell. 3.       Determination of Stefan's constant (Black body method). 4.       Study of the temperature dependence of resistivity of a semiconductor using four probe-methods. 5.       Study of Iodine spectrum with the help of grating and spectrometer and ordinary bulb light. 6.       Study of characteristics of a GM counter and verification of inverse square law for the same strength of a radioactive source. 7.       Study of β-absorption in Al foil using GM Counter to find endpoint energy. 8.       To find the magnetic susceptibility of a paramagnetic solution usi...

 . B.Sc. V Semester (Physics Lab) 1.       Verify Kirchhoff's laws using breadboard circuits with resistors and voltage sources. 2.       Verify the maximum power transfer theorem. 3.       Study the characteristics of a given transistor (PNP/NPN) in common emitter, common base, and common collector configurations. 4.         Determine the band gap of a semiconductor using a junction diode. 5.        Study the variation of gain with frequency in a single-stage transistor audio amplifier. 6.         Study the temperature dependence of resistance in a semiconductor using the four-probe method. 7.       Study the characteristics of a junction diode and a Zener diode. 8.       Study the characteristics of a field effect transistor (FET) and design an amplifier with finite ga...

 . B.Sc. IV Semester (Physics Lab) 1.       To study the Faradays Law of electromagnetic induction. 2.       To study the variation of power transfer by two different loads by a D.C. source and to verify the maximum power transfer theorem. 3.       To study the variation of charge and current in an RC circuit with a different time constant (using a DC source). 4.       To study the behaviour of an RC circuit with varying resistance and capacitance using AC mains as a power source and also to determine the impedance and phase relations. 5.       To study the rise and decay of current in an LR circuit with a source of constant emf. 6.       To study the voltage and current behaviour of an LR circuit with an AC power source. Also determine power factor, impedance and phase relations. 7.       To study the magneti...