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A Confocal Microscopy or Confocal Laser Scanning Microscopy (CLSM) uses pinhole to block out all out of focus light to enhance optical resolution, very different from traditional wide-field fluorescence microscopes. To offset the block of out of focus lights, the light intensity is detected by a photomultiplier tube or avalanche photodiode, which transforms the light signal into an electrical one. We will try to build a Setup like this to enhance optical resolution and maybe get profile information about the sample.
A Confocal Microscopy or Confocal Laser Scanning Microscopy (CLSM) uses pinhole to block out all out of focus light to enhance optical resolution, very different from traditional wide-field fluorescence microscopes. To offset the block of out of focus lights, the light intensity is detected by a photomultiplier tube or avalanche photodiode, which transforms the light signal into an electrical one. We will try to build a Setup like this to enhance optical resolution and maybe get profile information about the sample.


===[[Measure index of refraction]]===
===[[An interferometric method for measuring the resonance frequency of vibrating system]]===


Members: Joel Auccapuclla, Xiaoyu Nie, Haotian Song, Nakarin Jayjong.
Members: Joel Auccapuclla, Xiaoyu Nie, Haotian Song, Nakarin Jayjong.
Use an interferometer to obtain the index of refraction of different materials, for instance air.
In this project, the resonance frequency of the vibrating system namely the vibration transducer is studied using a Michelson interferometer.


===[[Homodyne detection]]===
===[[Homodyne detection]]===

Revision as of 14:37, 2 March 2022

MediaWiki has been installed. Welcome to the main page for the PC5214 graduate module AY2122, Sem2. Here, we leave project descriptions, literature references, and other collateral information. You will need to create an account in class to obtain write access.

Actual lecture locations will be placed here until we have reached a stable state. If you are interested and have not been able to register, please send me an email (if you have not done so already) to phyck@nus.edu.sg.

For the session on 14 Jan and some following sessions, we were given LT29.

Cheers, Christian

This page is currently set up.

Lab spaces

  • S11-02-04 (next to physics dept resource room). This is where most optics-related projects should go.
  • S12 level 4, "year 1 teaching lab", back room, "vanderGraff lab". This is perhaps were non-optics related projects would fit.
  • S13-01-?? (blue door: former accoustics lab). Not sure yet who could go there, but it is a really really quiet place!
  • anything else you have access to

Projects

Please leave a a link to your project page (or pages) here, and leave a short description what this is about. Write the stuff you need under the description too.

Project 1 (example)

Keep a very brief description of a project or even a suggestion here, and perhaps the names of the team members, or who to contact if there is interest to join.

Confocal Microscopy

Team Members: Wang Tingyu, Xue Rui, Yang Hengxing

A Confocal Microscopy or Confocal Laser Scanning Microscopy (CLSM) uses pinhole to block out all out of focus light to enhance optical resolution, very different from traditional wide-field fluorescence microscopes. To offset the block of out of focus lights, the light intensity is detected by a photomultiplier tube or avalanche photodiode, which transforms the light signal into an electrical one. We will try to build a Setup like this to enhance optical resolution and maybe get profile information about the sample.

An interferometric method for measuring the resonance frequency of vibrating system

Members: Joel Auccapuclla, Xiaoyu Nie, Haotian Song, Nakarin Jayjong. In this project, the resonance frequency of the vibrating system namely the vibration transducer is studied using a Michelson interferometer.

Homodyne detection

Proposed By: John Khoo

Optical homodyne detection is a method for detecting messages transmitted in optical signals, where a frequency or phase modulated signal is compared to what is misleadingly called the "local oscillator" (LO) signal, which is generated from the same source but not modulated with the message. In order to probe quantum effects, it is important to bring the noise of the detector down to the shot-noise limit, where the only fluctuations observed arise from the discrete nature of photons, which can be theoretically modelled as the vacuum-state fluctuations of the quantised electromagnetic field. This project's first objective is to build a homodyne detector from scratch.

Stuff we need: Acousto-optical modulator, electro-optical modulator, transformer to control EOM, photodiodes, current-to-voltage converter (I'm not sure what this is - can we just use a resistor connected to the ground and measure the voltage?), Raspberry Pi (I hope the ADC is good enough for this), mirrors and beamsplitters

Laser Microphone

Team Members: Nicholas Chong Jia Le, Marcus Low Zuo Wu

A laser spot illuminating a vibrating surface should move along with it, and tracking the motion of the spot should theoretically allow us to retrieve some of the information regarding the vibrations of the surface. If a loud enough sound causes the surface to vibrate, this should theoretically be enough for the transmission of audio information through visual means. We have a few different methods through which we will attempt to realise this.

Plasma emission spectroscopy

Proposed By: Park Kun Hee

Pulsed plasma in partial vacuum is characterised, by analysing line intensity ratios to determine its temperature and density.

Characterization of Single Photon Counters

Proposed By: Yeo Zhen Yuan (Looking for Teammates!)

The project is to characterize an Avalanche PhotoDiode (APD) and compare its efficiency with commercial counterparts like this device. It works based on the photoelectric effect to turn incident photon into photoelectron. This photoelectron is then accelerated in an electric field to produce cascading electrons and this "electron avalanche" is detected as a spike in the current. Analog signals will need to be processed via custom electronics and ultimately provide a digital readout. Current commercial detectors boast 50% Photon Detector Efficiency (PDE) at room temperature and that will be our goal. They typically cost $2000-$5000 which seems over-priced and ready for disruption. Liquid nitrogen temperatures may be needed to see how large a PDE we can get.

What is SPCM good for? Copied from the datasheet/brochure: LIDAR, Quantum Cryptography, Photon correlation spectroscopy, Astronomical observation, Optical range finding, Adaptive optics, Ultra-sensitive fluorescence, Particle sizing, Microscopy. So maybe this would become a toy/tool for next year's students.

Kerr Microscope

Proposed By: Sim May Inn (write up by Joel Yeo)

Team members: Gan Jun Herng, Joel Yeo

Project Location: S11-02-04

Imaging a sample can be done in many ways, depending on the light-matter interaction we are interested in observing. The magneto-optic Kerr effect describes the change in polarization and intensity of incident light when it impinges on the surface of a magnetic material. The resultant reflected light can then form an image through focusing optics which provides high contrast between areas of different magnetization.

In this project, we will be aiming to build a basic Kerr microscope using off-the-shelf polarizers, objectives, detectors and laser source. An example of a magnetic sample is the magnetic tape from an old school cassette tape. To increase the field of view, we also plan to incorporate automatic raster scanning of the sample through means of an Arduino-controlled sample stage.

Items needed (as of 28 Feb 2022):

  • Light source (visibile wavelength): Laser, LED , laser diode
  • Linear polarizer (sheet) x 2Camera (CCD/CMOS)
  • Non-polarizing beam splitter
  • Camera (CCD/CMOS)
  • Pinhole/aperture
  • Magnetic samples for Kerr microscopy (eg. Magnetic film, magnets, ferromagnetic materials)
  • Arduino
  • Microscope stage
  • Piezoelectrics (?) for moving stage

Electron Gun

Team Members: Aliki Sofia Rotelli, Lai Tian Hao, Lim En Liang Irvin, Tan Chuan Jie

The purpose of this project is to design and build an electron gun from the initial concept in order to create a detectable electron beam through the use of a phosphor-coated screen. Additionally, the beam current will be examined in order to better define the devices' capabilities. Mass spectrometry, x-ray production for linear accelerators, and electron-beam lithography are just a few of the applications for electron gun technology.

Air biased coherent detection

Team Members: Cheng De Hao, Huang Hai Tao, Wang Zhenyu

In-situ magnetic imaging and Hall detection

Proposed by Sim May Inn

In computing and memory device architectures, propagation of magnetic domains play an essential role in the encoding and transport of information. Magnetic domain imaging is often employed to unveil such propagation dynamics. Additionally, other than observation and studies of their dynamics, means of detection are also of interest, and this can be achieved through the read-outs of Hall effect signals. As such, this project aims to design and modify an existing low temperature setup to be able to concurrently perform both magnetic domain imaging and Hall signal detection.

Anti-glare LCD

Team members: Zhang Yuanyuan, Ming Xiaohan, Han Shixin

As s bad lighting phenomenon, glare phonomenon brings inconvenience to all aspects of human life, especially people's access to information on instruments. In order to suppress glare effectively, anti-glare film is put into research. The common anti-glare film in the market is an optical film using the principle of optical scattering, but it can not adapt to the change of light environment in time, which has some limitations in practical application. In this study, a two-dimensional barcode micro-region orientation structure, based on the characteristics of liquid crystal, namely a random grating structure, was designed by simulation in the lab and using MATLAB software, and its optional parameters were searched.

Custom atomic beam source

Team Members: Lu Tiangao, Li Putian

Schlieren imaging

Team members: Zhang Xingjian, Du Jinyi

Contactless Conductivity Measurement

Team members: Chen Guohao, Jiang Luwen

The purpose of this project is to measure the conductivity of materials without having to make electrical contact with them. Specifically, we make use of the eddy-current induced in the materials to calculate the conductivity.

Quantum Random Number Generator

Team members: Wang Yang, Xiao Yucan, Zhang Munan

Random numbers are a fundamental resource in science and engineering with important applications in simulation and cryptography. The inherent randomness at the core of quantum mechanics makes quantum systems a perfect source of entropy. Quantum random number generation is one of the most mature quantum technologies with many alternative generation methods. The purpose of our project is to build a simple optics-based QRNG. We will also collect the random number generated by our device and use some methods to check the randomness.

Orbits of the Galilean Moons

Team Members: Matthew Wee

Galileo Galilei’s discovery of celestial bodies that orbit something other than the Earth marked the beginning of the end of the geocentric model of the universe. In this project, we will perform the same observations on those moons as Galileo did 400 years ago.

Resources

Recorded sessions

Some of the sessions will be recorded and uploaded to youtube. Find a description on the Recorded sessions page.

Devices and material

Apart form all the stuff in the teaching lab, we have a few resources you may want to consider for your project

  • ...

Books:

  • P.R. Bevington, D.K. Robinson: Data Reduction and Error Analysis for the Physical Sciences, 3rd edition. McGrawHill, ISBN0-07-119926-8. A very good book containing all the questions you never allowed yourself to ask about error treatment, statistics, fitting of data to models etc.
  • Horrowitz/Hill: The Art of Electronics
  • C.H. Moore, C.C. Davis, M.A. Coplan: Building Scientific Apparatus. 2nd or higher edition. Perseus Books, ISBN0-201-13189-7. A very comprehensive book about many dirty details in experimental physics, and ways to get simple problems solved. Appears a bit dated, but is a good start for many experimental projects up to this day!
  • Christopher C. Davis: Laser and Electro-optics. Useful as a general introduction to many contemporary aspects you come across when working with lasers, with a reasonable introduction of the theory. Very practical for optics.

Software: Some of the more common data processing tools used in experimental physics:

  • Gnuplot: A free and very mature data display tool that works on just about any platform used that produces excellent publication-grade eps and pdf figures. Can be also used in scripts. Open source and completely free.
  • Various Python extensions. Python is a very powerful free programming language that runs on just about any computer platform. It is open source and completely free.
  • Matlab: Very common, good toolset also for formal mathematics, good graphics. Expensive. We may have a site license, but I am not sure how painful it is for us to get a license for this course. Ask me if interested.
  • Mathematica: More common among theroetical physicists, very good in formal maths, now with better numerics. Graphs are ok but can be a pain to make looking good. As with Matlab, we do have a campus license but an increasingly painful licensing ritual. Ask me if interested or follow the instruction to install the software in your desktop.
  • Origin: Very widespread data processing software with a complete graphical user interface, integrates well into a Windows environment. Most likely available in your research labs, not sure if NUS has a site license.
  • Labview: Many of you may have seen this in your labs, but I am not too familiar with it, and chances are it is too resource-hungry to run on the machines we have there. It keeps its promise of a fast learning curve if you want to do simple things but it can get a REAL pain if you want to do subtle things, or want to do things fast, or want to debug code. Expensive and resource-hungry, but comes with good integration of also expensive hardware. May not be worth it if you know any programming language.
  • Circuit Lab: a convenient software to design and simulate electrical circuits directly at your browser. I think Flash is required. It works well in Chrome.

Acronym database

This is an attempt to clarify the countless acronyms we use in our sub-communities (follow headline link)


Gnuplot tricks

Follow the headline link for some of the random questions that came up with gnuplot.

Previous PC5214 wikis

Some wiki reference materials

Consult the User's Guide for information on using the wiki software. Other sources: