Build Your Own Quantum Computer for Fun and Profit! Stephen Granade

Bits are 1s and 0s (i.e. base 2) 16 8 4 2 1 1 1 1 16 2 1 + + = 19

Save Us, Gordon Moore!

Parallel Computation Takes More Space Photo credit: pure_martin

Light Polarization States Vertical light: Horizontal light: A mix: Amplitudes Square for probabilities:

What’s Going On With The 3 Polarizers Vertical polarizer: Horizontal polarizer: nada

What’s Going On With The 3 Polarizers Vertical polarizer: 45 degree polarizer: Horizontal polarizer:

Bits Hold 1 Number Qubits Can Hold All Numbers! 3-Bit Number 3-Qubit Number Superposition makes this possible

Tangent: Entanglement Happens When One Qubit’s State Depends on Another’s Entangled Not Entangled If you measure the first qubit and it’s 0, you know the second qubit is 0 too. They’re entangled! If you measure the first qubit and it’s 0, you don’t know the second qubit. They’re independent!

You Can Add All Numbers At Once! Classical Computer Quantum Computer

It’s Just an Algorithm Public Private

Turning Factoring into Period Finding If n has the factors p and q, then, if you pick a random x, the above sequence has a period that evenly divides into (p-1)(q-1) Leonhard Euler

Shor’s Algorithm is Fast Classical factoring Shor’s Algorithm

Grover’s Algorithm Finds Stuff Quickly Searches unsorted data Number of items Approx. Speedup 100 10 1,000 32 10,000 100,000 316 1,000,000 1000 10,000,000 3162 100,000,000 10000 1,000,000,000 31623 Photo credit: seanabrady

Decoherence Smears Out States

There are Lots of Ways to Make a Quantum Computer Photons Trapped Ions Optical Lattice Liquid NMR Spintronics

7-Qubit Computer from IBM 2001. Chuang et. al. Factored 15 3 5

First Qubyte from Innsbruck

Quantum Computer Onna Chip Sadly I have no good pictures of the group or its research besides this graphic from the cover of Science

D-Wave…maybe