Merge pull request #9 from EarlOld/bell-states

Added Bell States

README.md

@@ -60,6 +60,16 @@ The library supports the following quantum gates, check the table below for the
 | Circuit.teleportationOneToTree   | Teleportation of a qubit from one quantum register to another                           |
 | optimizeQAOAWithCOBYLA           | Optimize the QAOA algorithm using the COBYLA optimization algorithm for Max-Cut problem |
 
+
+## Bell State Functions
+
+| Functions                | Description                                                                 |
+| ------------------------ | --------------------------------------------------------------------------- |
+| Circuit.prepareBellPhiPlus | Prepare the Bell state Phi+                                             |
+| Circuit.prepareBellPhiMinus | Prepare the Bell state Phi-                                             |
+| Circuit.prepareBellPsiPlus | Prepare the Bell state Psi+                                             |
+| Circuit.prepareBellPsiMinus | Prepare the Bell state Psi-                                             |
+
 ## Dependencies
 
 The library uses the following dependencies:

docs/pages/examples/bellStates.mdx

@@ -0,0 +1,101 @@
+# Bell States
+
+## Description
+
+The Bell states are four specific maximally entangled quantum states of two qubits. They are in a superposition of 0 and 1, and are the maximally entangled states. The Bell states form an orthonormal basis for the two qubits, and when one qubit is measured, the outcome of the other qubit is immediately known, no matter how far apart the qubits are.
+
+## Parameters
+
+- `first` (Type: `number`) - The first qubit index.
+- `second` (Type: `number`) - The second qubit index.
+
+## Example 1 - Prepare Bell Phi Plus State
+
+### Code
+
+```typescript
+import { Circuit } from '@earlold/quantum.js';
+
+const circuit = new Circuit(2);
+circuit.prepareBellPhiPlus(0, 1);
+circuit.run();
+console.log(circuit.stateToString);
+```
+
+### Output
+
+```console
+0.00000000+0.00000000i|00>       0.00000%
+0.70710678+0.00000000i|01>      50.00000%
+0.70710678+0.00000000i|10>      50.00000%
+0.00000000+0.00000000i|11>       0.00000%
+```
+
+## Example 2 - Prepare Bell Phi Minus State
+
+### Code
+
+```typescript
+import { Circuit } from '@earlold/quantum.js';
+
+const circuit = new Circuit(2);
+circuit.prepareBellPhiMinus(0, 1);
+circuit.run();
+console.log(circuit.stateToString);
+```
+
+### Output
+
+```console
+0.70710678+0.00000000i|00>      50.00000%
+0.00000000+0.00000000i|01>       0.00000%
+0.00000000+0.00000000i|10>       0.00000%
+-0.70710678+0.00000000i|11>      50.00000%
+```
+
+## Example 3 - Prepare Bell Psi Plus State
+
+### Code
+
+```typescript
+import { Circuit } from '@earlold/quantum.js';
+
+const circuit = new Circuit(2);
+circuit.prepareBellPsiPlus(0, 1);
+circuit.run();
+console.log(circuit.stateToString);
+```
+
+### Output
+
+```console
+0.00000000+0.00000000i|00>       0.00000%
+0.70710678+0.00000000i|01>      50.00000%
+0.70710678+0.00000000i|10>      50.00000%
+0.00000000+0.00000000i|11>       0.00000%
+```
+
+## Example 4 - Prepare Bell Psi Minus State
+
+### Code
+
+```typescript
+import { Circuit } from '@earlold/quantum.js';
+
+const circuit = new Circuit(2);
+circuit.prepareBellPsiMinus(0, 1);
+circuit.run();
+console.log(circuit.stateToString);
+```
+
+### Output
+
+```console
+ 0.00000000+0.00000000i|00>       0.00000%
+-0.70710678+0.00000000i|01>      50.00000%
+ 0.70710678+0.00000000i|10>      50.00000%
+ 0.00000000+0.00000000i|11>       0.00000%
+```
+
+
+

docs/theme.config.tsx

@@ -11,7 +11,7 @@ const config: DocsThemeConfig = {
   },
   docsRepositoryBase: 'https://github.com/EarlOld/quantum.js',
   footer: {
-    text: 'MIT 2024 © EarlOld - [email protected].1',
+    text: 'MIT 2024 © EarlOld - [email protected].2',
   },
 };
 

library/__tests__/circuit.test.ts

@@ -60,4 +60,47 @@ describe('Circuit', () => {
 
   //   expect(randomString.length).toEqual(10);
   // });
+
+  it('should make bell state PhiPlus', () => {
+    const circuit = new Circuit(2);
+    circuit.prepareBellPhiPlus(0, 1);
+    circuit.run();
+
+    const state = circuit.stateToArray();
+    expect(state[0].chanceStr).toEqual('50.00000');
+    expect(state[3].chanceStr).toEqual('50.00000');
+  });
+
+  it('should make bell state PhiMinus', () => {
+    const circuit = new Circuit(2);
+    circuit.prepareBellPhiMinus(0, 1);
+    circuit.run();
+
+    const state = circuit.stateToArray();
+    expect(state[0].chanceStr).toEqual('50.00000');
+    expect(state[3].chanceStr).toEqual('50.00000');
+  });
+
+
+  it('should make bell state PsiPlus', () => {
+    const circuit = new Circuit(2);
+    circuit.prepareBellPsiPlus(0, 1);
+    circuit.run();
+
+    const state = circuit.stateToArray();
+    expect(state[1].chanceStr).toEqual('50.00000');
+    expect(state[2].chanceStr).toEqual('50.00000');
+  });
+
+  it('should make bell state PsiMinus', () => {
+    const circuit = new Circuit(2);
+    circuit.prepareBellPsiMinus(0, 1);
+    circuit.run();
+
+    const state = circuit.stateToArray();
+    expect(state[1].chanceStr).toEqual('50.00000');
+    expect(state[2].chanceStr).toEqual('50.00000');
+  });
+
+
 });

library/circuit.ts

@@ -1,5 +1,7 @@
 import QuantumCircuit from 'quantum-circuit';
 
+import { ObjectQubitState } from './types';
+
 export class Circuit {
   private quantumCircuit: QuantumCircuit;
 
@@ -71,6 +73,14 @@ export class Circuit {
     return this.quantumCircuit.measureAll();
   }
 
+  public stateToString(): string {
+    return this.quantumCircuit.stateAsString(false) as string;
+  }
+
+  public stateToArray(): ObjectQubitState[] {
+    return this.quantumCircuit.stateAsArray(false, undefined, undefined, undefined) as ObjectQubitState[];
+  }
+
   public toQsharp(): string {
     return this.quantumCircuit.exportQSharp('quantum.js', false, null, null, false, null);
   }
@@ -79,6 +89,48 @@ export class Circuit {
     return this.quantumCircuit.exportSVG(true);
   }
 
+  // Bell states
+
+  public prepareBellPhiPlus(first: number, second: number): void {
+    if (first === second) {
+      throw new Error('The qubits must be different');
+    }
+
+    this.h(first);
+    this.cx(first, second);
+  }
+
+  public prepareBellPhiMinus(first: number, second: number): void {
+    if (first === second) {
+      throw new Error('The qubits must be different');
+    }
+
+    this.h(first);
+    this.z(first);
+    this.cx(first, second);
+  }
+
+  public prepareBellPsiPlus(first: number, second: number): void {
+    if (first === second) {
+      throw new Error('The qubits must be different');
+    }
+
+    this.h(first);
+    this.x(second);
+    this.cx(first, second);
+  }
+
+  public prepareBellPsiMinus(first: number, second: number): void {
+    if (first === second) {
+      throw new Error('The qubits must be different');
+    }
+
+    this.h(first);
+    this.z(first);
+    this.x(second);
+    this.cx(first, second);
+  }
+
   public static genRandomNumber(max: number): number {
     // Generate a random number between 0 and max
     // Max to binary

library/types/index.ts

@@ -0,0 +1,11 @@
+export type ObjectQubitState = {
+  index: number;
+  indexBinStr: string;
+  amplitude: { re: number; im: number };
+  amplitudeStr: string;
+  magnitude: number;
+  chance: number;
+  chanceStr: string;
+  phase: number;
+  phaseStr: string;
+};

package.json

@@ -1,7 +1,7 @@
 {
   "name": "@earlold/quantum.js",
   "type": "module",
-  "version": "0.3.1",
+  "version": "0.3.2",
   "description": "Quantum.js is a library for quantum computing",
   "main": "index.js",
   "repository": "https://github.com/EarlOld/quantum.js",

src/index.ts

@@ -1,19 +1,7 @@
-import { optimizeQAOAWithCOBYLA } from 'library';
+import { Circuit } from 'library';
 
-const nodes = [0, 1, 2, 3, 4];
-const edges: Array<[number, number]> = [
-  [0, 3],
-  [0, 4],
-  [1, 3],
-  [1, 4],
-  [2, 3],
-  [2, 4],
-];
-const steps = 1;
+const circuit = new Circuit(2);
+circuit.prepareBellPsiMinus(0, 1);
+circuit.run();
 
-const { beta, gamma, score, maxCutScore } = optimizeQAOAWithCOBYLA(nodes, edges, steps);
-
-console.log('Optimized beta:', beta);
-console.log('Optimized gamma:', gamma);
-console.log('Best score:', score);
-console.log('maxCutScore:', maxCutScore);
+console.log(circuit.stateToString());