Table 2 The coefficients of the optimised states with \({n}_{\max }=7\) photons.

From: Surpassing the repeaterless bound with a photon-number encoded measurement-device-independent quantum key distribution protocol

Distance

a0

a1

a2

a3

a4

a5

a6

a7

(km)

b0

b1

b2

b3

b4

b5

b6

b7

0

0.0823

0.1162

0.1432

0.1582

0.1582

0.1432

0.1162

0.0823

0.5

0.1073

0.1359

0.1557

0.1603

0.1496

0.1267

0.0968

0.0676

1

0.1226

0.1472

0.1616

0.1600

0.1438

0.1174

0.0868

0.0605

2.5

0.1550

0.1705

0.1710

0.1567

0.1307

0.0994

0.0691

0.0477

5

0.1967

0.2012

0.1786

0.1483

0.1129

0.0787

0.0508

0.0329

10

0.4468

0.3137

0.1410

0.0601

0.0245

9.4433 × 10−3

3.3895 × 10−3

1.1308 × 10−3

15

0.6654

0.2955

0.0366

2.4273 × 10−3

1.1213 × 10−4

3.9036 × 10−6

9.8873 × 10−8

0

20

0.7230

0.2608

0.0160

2.8606 × 10−4

2.1895 × 10−6

3.2584 × 10−9

0

0

25

0.7548

0.2366

8.5496 × 10−3

4.9545 × 10−5

6.2159 × 10−8

0

0

0

30

0.7760

0.2189

5.0283 × 10−3

1.0464 × 10−5

0

0

0

0

50

0.8176

0.1811

1.3468 × 10−3

1.2642 × 10−7

0

0

0

0

100

0.8477

0.1520

3.3582 × 10−4

0

0

0

0

0

200

0.8571

0.1427

1.9467 × 10−4

0

0

0

0

0