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Liu et al. J Mater Inf 2022;2:20 https://dx.doi.org/10.20517/jmi.2022.29 Page 7 of 12

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Figure 3. Correlation between T and D (Δt). (A): Snapshot of a HEMG slice with the thickness of 3.8 Å, in which the atoms are
ML 2 min
colored by T ; (B-E): colored by D (Δt), at Δt = 5, 20, 50, 100 ps, respectively; (F): correlation coefficients between T and
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ML min ML
D (Δt). The results are from the simulation at T = 100 K and σ = 2.3 GPa. ML: Machine learning.
min h
heterogeneity of atomic dynamics. To unfold the correlation between atomic dynamics and local inelastic
[42]
2
deformation, we computed the non-affine displacement D (∆t) ,
min

where CN is the coordination number, determined from partial radial distribution functions, as shown in
Supplementary Figure 4; the subscript index j runs over the nearest neighboring atoms; j = 0 denotes the
2
reference atom; J is the locally affine transformation matrix. Figure 3B-E visualizes D (∆t) on the same
2 min
sample slice as shown in Figure 3A. Due to D (∆t) usually acting as a symbol of local inelasticity, we can
min
observe an increasing number of inelastic deformations occur, and the severely deformed spots gradually
[42]
enlarge with enhanced interactions . The mounting similarity between the spatial distribution of T and
ML
2
D (∆t) proves that the inactive “cold” matrix gives the elastic response to the applied stress, and the active
min
“hot” atoms trigger the local inelastic events. As shown in Figure 3F, the Pearson correlation coefficients ξ
2
between T and D (∆t) further corroborate their close connection, which is calculated from the
ML min
c o v a r i a n c e c o v ( x , y) a n d t h e s t a n d a r d d e v i a t i o n σ ( x) a s e x p r e s s e d b y

,
2 2
ξ = cov(T , D (∆t))/σ(T )σ(D (∆t)). The positive value of ξ means that the atoms with a higher T are
ML min ML min ML
more likely to participate in the local inelastic deformation. In contrast, the low-T atoms prefer moving in
ML
an affine manner. Therefore, the atomic scale mechanism of the stress-induced viscoplastic flow should be
the cooperative motion of high-T atoms. As the creep time goes by, ξ increases from ~0.24 to ~0.49.
ML
-1 [34]
-1
However, the growth rate of ξ is 0.0025 ps , which is slower than that of Cu Zr (~0.003 ps ) . It turns out
50 50
that the active “hot” atoms in HEMGs make an inefficient and sluggish contribution to the local plasticity,
compared with conventional MGs.
Structural characteristics of LAs and SAs
The atoms of the same type are identical particles, and thus their difference in atomic dynamics should
result from the surroundings, such as coordination, local symmetry, and chemical ordering. To characterize