Experiments

List of experiments used for the chapter outreach activities

# Experiment Description Current whereabouts and status
E1 Water jet/total reflection A laser pointer is pointed towards a basin that has a pipe that lets water flow to the outside. The water jet forms a parabola due to the gravity and is collected by a basin on the floor. The laser light is pointed towards the water jet and total internal reflection is shown. ·         Office of Vanessa Chille

·         Stuff needed:

·         Breadboard with basins

·         Laser pointer

·         Pump

·         Power supply

E2 Bouncing laser in sugar solution graded refractive index

 

A basin is filled with a sugar solution to create a graded index liquid. A laser pointer is coupled in from the side of the basin. The laser light gets refracted towards the bottom of the basin and then reflected, creating a “bouncing light” impression. ·         In one of the Sandoghdar offices?

·         Water basin

·         Sugar solution in canisters for transport

·         Laser pointer

E3 MPL Holograms for laser pointers A hologram is put onto a laser pointer such that an MPL logo spatial mode is created. ·         Betti has the hologram

·         Tom has the hologram mount

E4 Hit spot in water basin Water has a different refractive index than air. As such, it is not so easy to hit a target inside a basin of water with a laser pointer. This would be a fun experiment for the Blue Night crowd to try out themselves. ·         Does not exist yet. Someone needs to build this

·         Stuff needed:

·         Water basin

·         Laser pointer

·         Target

E5 Crossed polarizers/Birefringence A white light source hits a 30x30cm polarizing sheet. The polarized light the travels through the encasing to finally hit another 90° crossed polarizer sheet. No light gets transmitted in this configuration. The fun is to hold objects in between and explain how they change the polarization and therefore the transmittance through the second polarizer. Birefringence causes nice colours. ·         Where is it?

·         Stuff needed:

·         The box with the polarizers

·         Samples to hold into the box (polarizer foil, plastic ruler, Glucose vial)

E6 Optical Cloaking Two lenses form an optical setup, behind which a printed grid is portrayed. When an observer holds his hand near the focus of the two lenses, it seems that the hand disappears behind the lens. ·         Hacking lab

·         Stuff needed:

·         Wooden strip to hold optics

·         Magnifying glass as lenses

·         Printed grid

·         Webcam

·         Laptop

E7 Optical 3D Hologram A smart phone, tablet or beamer light source with an animation playing is pointed at a sheet of plexiglass at 45° aoi. The observer looks at the reflection and the image appears behind the plexiglass like a “3D hologram”. ·         Borrowing a big beamer setup from the university

·         Little plastic foil holograms need to be printed/assembled as giveaways

·         MPL Minerva animation needs to be done in a 3D studio and uploaded on youtube and

E8 Listening to quantum noise A bright laser beam is pointed at a photo diode. The power is chosen such that the shot noise power exceeds the electronic noise of the detector. Assuming shot noise limited operation and amplifying the detected noise, one may listen to the quantum vacuum noise.

Additionally, there is the possibility to modulate sound onto the laser beam and make it audible on the receiving end.

·         Probably with Kevin Günthner or Christian Müller

·         Stuff needed:

·         Kevin knows best…

E9 Laser microphone A speaker is kept inside a plexiglass box, causing the box to vibrate from the sound. A laser is pointed at the box from the outside at an angle. The sound displaces the window and causes a displacement of the laser beam. A photo diode measures the laser beam and sees an amplitude modulation caused by the displacement. An audio amplifier is attached to the photo diode to make the sound inside the box audible. ·         Located on window shelf in Imran’s office

·         Stuff needed:

·         Breadboard with everything mounted on it

·         Laserpointer (with power plug), currently with Betti; mount needs to be adjusted/tested for new source

·         Mp3 player

·         Headphones

E10 Google cardboard Virtual reality goggles are expensive. Google realized that they require just a display, some motion sensors, two lenses and a frame. All those things can be found in a smart phone. Just put your phone into one of the Google cardboard frames with two lenses inside and you have a cheap VR headset. ·         Imran has two cases at home

·         Valentin: do you have one?

·         Otherwise, we need a smart phone with the proper apps installed for that

E11 Laser graffiti A laser pointer is pointed at a beamer screen. A webcam tracks the position of the laser pointer with a dedicated software. The software then changes the color at the position of the laser pointer. People can paint J ·         Stuff needed:

·         Laptop

·         Webcam

·         Beamer + Screen (will be the same as for the talks; Selda has ordered the screen)

·         Laser pointer + Batteries