Table 1 Performance comparison of PNNs for benchmark tasks

From: Physical deep learning with biologically inspired training method: gradient-free approach for physical hardware

 

Data set

Training method

MNIST

Fashion MNIST

Cifar-10

PNN based on photonics

Deep RC [sim.] (this study)

98.96 % (w/o preprocessing)

86.52%

55.80%

Augmented DFA (with optoelectronic hardware)

Deep RC [exp.] (this study)

97.80% (w/o preprocessing)

85.91%

47.83%

Diffractive photonic DNN

96.6 % [exp.]34 (w/o preprocessing)

84.6% [exp.]34

44.4% [exp.]69

BP (on external standard computer)

On-chip photonic DNN

95.3% [exp.]66 (w/o preprocessing)

Not reported

Not reported

Large-scale Photonic RC

97.15% [sim.]68 (w/o preprocessing) 98.90% [exp.]68 (with preprocessing)

Not reported

Not reported

Linear regression (on external standard computer)

On-chip Photonic RC

91.3% [exp.]35 (w/o preprocessing)

70.1% [exp.]35

Not reported

RC based on other physical dynamics

Spintronic RC

87.6% [sim.]65 (w/o preprocessing)

Not reported

Not reported

Linear regression (on external standard computer)

Memristor RC

88.1% [exp.]64 (w/o preprocessing)

Not reported

Not reported

Diffusive memristor RC

83% [exp.]67 (w/o preprocessing)

Not reported

Not reported

Self-organized nanowire RC

90.4% [exp.]63 (w/o preprocessing)

Not reported

Not reported

SOTA model on standard computer (PNNs not used)

99.91% (Ensembled CNN70)

95.99% (ResNet-11071)

98.9% (Efficient Net72)

BP (all computations done by standard computer)

  1. Scores for MNIST, Fashion MNIST, and CIFAR-10 for our device. The node counts were set to 101, 202, 404, 606, 808, and the layer number was 1–5. For comparison, the reported scores for PNNs based on photonics and an RC based on other dynamics are also shown34, 35, 63,64,65,66,67,68,69. As references, the table shows the state-of-the-art results obtained with standard computers for these benchmarks70,71,72. The features of our approach are high performance even in a simple optical implementation and training based on optoelectric dynamics, which can accelerate both inference and training speed. Sim. and exp. means simulation and experimental results. Preprocessing means image processing before physical inputs such as a Gabor filter68, which can enhance performance. For a fair comparison, we focused on the results without preprocessing.