| General research and development: |
Circuit boxes: We make our own circuit boxes depending on the demand in the lab. Boxes are made out of plexiglass or aluminium sheet.
Furaces: We have a muffle and vacuum tube furnace which are 30 step programmable.
Ferroelectric materials: We can make ferroelectric materials using Solgel autocombustion.
Power tools and machining facility: We have acquired a whole range of power tools and a top of the line manual gear head lathe, resources that help us in all modifications and manufacturing of minor to moderate levels.
Optical table: We have acquired an optical table for our optical experiments. A variety of optical breadboards are also available.
Resource for LUMS: We also act as a resource for other labs in their research experiments.
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| Faraday rotation: |
The Faraday effect is a magneto-optical phenomenon. It is the rotation of plane of polarization of linearly polarized light transmitting through an optically inactive medium under the action of an axial magnetic field and is usually very small in magnitude, of the order of micro radians. With the help of the lock-in technique and using a small ac magnetic field, this requirement can be bypassed. We have devised an experiment using phase sensitive technique to study the historically important Farday rotation in different materials.
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| Electrical suceptibility measurments: |
Our freshman experiment on the measurement of the Curie temperatures was very popular. Currently, we are adding susceptibility measurements to the experiment, enabling us to look at the temperature dependent susceptibility. Further, we are also developing a dynamical model for the thermocouple's thermal inertia applicable in rapid heating conditions. |
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| AFM Development: |
AFM (Atomic Force Microscope) is used in very high resolution microscopy, with typical resolution of 0.16 nanometer. With different operational modes AFM can be used to image almost any type of samples from solid metals to biomedical specimens. The physlab is developing a teaching and basic-research grade AFM in-house. The basic principle lies on cantilever deflection when scanned very close to the sample. A laser beam is used to detect the deflection of cantilever by using photo detector.
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| Measurement of energy band gap in semiconductors : |
We are designing an experiment for the fast and reliable measurements of the temperature dependence of electrical conductivity in semiconductor and metallic samples. The energy band gap can be calculated from the data taken in the intrinsic region, and the temperature dependence of the majority carrier mobility can be deduced from measurements taken in extrinsic region. Important parameters are, temperature controlling which is being done by using ‘Multi-Zone Controller’ and resistance measurement using ‘Four Probe Method’.
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| Heaters and micro-ovens: |
We are perfecting in the art of cartridge and disk heater design. Currently we can make cartridge heaters ranging from 4 mm in diameter and 20 mm in length to 20 mm in diameter and 300 mm in length. All heaters are made on demand and we also make these for other departments. With additional equipment we can introduce temperature control also. We are also developing `temperature stable' cavities as small as 20 mm in diameter and 50 mm in length for temperatures ranges of -196 Deg C to 500 Deg C.
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| Determination of Avogadro’s number: |
In this experiment we will use a suspension of uniform Polystyrene Microspheres and with the help of microscope objective, CCD camera and computer software we will determine the position of microspheres. By incorporating the mean square displacement of suspended particles in the Einstein’s formula we will calculate the Avogadro’s number. This formula was derived by applying the van’t Hoff law to suspensions, assuming Stoke’s law and describing the Brownian motion as a diffusion process.
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| Chromium's antiferromagnetic to paramagnetic phase transition: |
Many physical substances undergo phase transition when subjected to heat. Chromium also follows that behavior which is associated with the change in its magnetic order. In this experiment we study the phase transition of Chromium by directly measuring the volume change at Neel temperature.
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| Muon lifetime measurement: |
SSE physlab is developing an experiment on muon life time measurement for junior physics lab. We are also developing a low cost-high speed electronics module based on fast complex programmable logic devices (CPLD) which will act as stand alone signal extracting and logic component in the experiment.
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| Cryoelectronics: |
Superconducting Quantum interference devices (SQUIDs) are sensitive devices that can detect small changes in the magnetic field. They take advantage of two important properties of superconductors, namely the flux quantization and the Josephson effect. Mr. SQUID is a commercially available high temperature superconducting (HTS) DC SQUID. We have used Mr. SQUID to study the novel phenomena of superconductors and have used is as an extremely sensitive magnetometer and nano-voltmeter.
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| Lattice vibrations experiment: |
The experiment is on Lattice vibrations and demonstrating phonons. The dispersion relation for the loaded spring (mono atomic and diatomic case) is investigated. The optical and acoustic curves are obtained experimentally. Vibrational patterns of strings, eigen frequencies measurement, band Gap and other localization properties are investigated. The normal modes of the string are found using normal mode analysis and pulse analysis. |
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| RL-Diode Chaotic Circuit: |
As an experiment in the nonlinear dynamics series, "Observing Chaos in an RL-Diode Circuit" is to be included in Experimental Physics Lab II. It beautifully manifests the notion of chaos and the related non-linearities. Bifurcations and chaos in circuit behavior are observed using different tools, e.g. Fourier Spectra, phase portraits and Poincare Sections as well as the dual mode plots on oscilloscope. |
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| Physiological Measurements: | .
The SSE Physlab is developing a low-cost unit that will teach students the technology behind the scenes in physiological measurements. Pulse oximetry and ECG units have already been demonstrated and new experiments are being added to the reportoire. This is in collaboration with Dr. Abubakr's group in Electrical Engineering |
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Research & Development - Page 2
