QuantumField is the head of quantized fields and their
derivatives.
QuantumField[par, ftype, {lorind}, {sunind}] denotes a
quantum field of type ftype with (possible) Lorentz-indices
lorind and SU(N) indices
sunind. The optional first argument par
denotes a partial derivative acting on the field.
Overview, FeynRule, FCPartialD, ExpandPartialD.
This denotes a scalar field.
QuantumField[S]S
Quark fields
QuantumField[AntiQuarkField]\bar{\psi }
QuantumField[QuarkField]\psi
This is a field with a Lorentz index.
QuantumField[B, {\[Mu]}]B_{\mu }
Color indices should be put after the Lorentz ones.
QuantumField[GaugeField, {\[Mu]}, {a}] // StandardForm
(*QuantumField[GaugeField, LorentzIndex[\[Mu]], SUNIndex[a]]*)A_{\Delta}^a is a short form for \Delta ^{mu } A_{mu }^a
Derivatives of fields are denoted as follows.
QuantumField[FCPartialD[LorentzIndex[\[Mu]]], A, {\[Mu]}]\left(\partial _{\mu }A_{\mu }\right)
QuantumField[QuantumField[A]] === QuantumField[A]\text{True}