  Some magnetic systems display a shift in the center of their magnetic
hysteresis loop away from zero field, a phenomenon termed exchange bias.
Despite the extensive use of the exchange bias effect, particularly in magnetic
multilayers, for the design of spin-based memory/electronics devices, a
comprehensive mechanistic understanding of this effect remains a longstanding
problem. Recent work has shown that disorder-induced spin frustration might
play a key role in exchange bias, suggesting new materials design approaches
for spin-based electronic devices that harness this effect. Here, we design a
spin glass with strong spin frustration induced by magnetic disorder by
exploiting the distinctive structure of Fe intercalated ZrSe2, where Fe(II)
centers are shown to occupy both octahedral and tetrahedral interstitial sites
and to distribute between ZrSe2 layers without long-range structural order.
Notably, we observe behavior consistent with a magnetically frustrated, and
multi-degenerate ground state in these Fe0.17ZrSe2 single crystals, which
persists above room temperature. Moreover, this magnetic frustration leads to a
robust and tunable exchange bias up to 250 K. These results not only offer
important insights into the effects of magnetic disorder and frustration in
magnetic materials generally, but also highlight as design strategy the idea
that a large exchange bias can arise from an inhomogeneous microscopic
environment without discernible long-range magnetic order. In addition, these
results show that intercalated TMDs like Fe0.17ZrSe2 hold potential for
spintronics technologies that can achieve room temperature applications.
