# How to make a double slit electron interference as a home experiment? [closed]

I want to see electron interference making my own experimental equipments.

Do you think it is possible?

Especially, double slit, how can I have it?

• I'm voting to close this question as off-topic because of insufficient research effort. – sammy gerbil Jul 25 '16 at 17:04
• Possible duplicate of Double slit experiment – RedGrittyBrick Jul 26 '16 at 10:26
• Not a duplicate as that one references light interference, not electron interference, and they are very different experiments. – entpnerd Sep 24 '16 at 7:30

OK you can do it. GP Thomson have done it long before. You need a low pressure vacuum tube to generate the cathode rays (electrons). An essential requirement and rather costly one. I am afraid that you have to make one (size ~500 mm).

To do this you need electrocathode (thermionic), resistive heating element, acrylic or glass tube, anode, a rotary vacuum pump and a vacuum gauge (pirani or diaphram), double slit.

Connect the heater to the cathode, place the cathode and anode appropriately in the tube.

Place the double slit (50 micron slit with 100 micron separation) in between the cathode and anode. This type of double slit might need laser cutting.

Place a phosphor before anode. You can coat Gadolinium Oxy Sulphate on a glass plate or use the available phosphors such as DRZ, Lanex screens etc.

Seal the tube appropriately using O-rings, vacuum pump the tube to $10^{-2}$ to $10^{-3}$ mbar. Heat the cathode to emit electrons and accelerate it to anode.

Use very low accelerating voltages ($\approx 1-5$ V), or the wavelength will be too small:

$$\lambda=\frac{h}{mv}$$

You should be able to see electron diffraction.

PS: You will also need vacuum feed-through for electrical connections, they are rather easy and can be made with a method known as potting. For potting you need a resin-hardner mixture based adhesive just make a hole in the acrylic put some metal pins and fill the hole with the adhesive let it dry for 24 hrs and you are done. You need to keep the metal pins such that it has clear ends both towards vacuum and towards air.