HLi6.hp42s

@ Calculate energy difference (in MHz) between the two 6Li(F=1/2) ground states.
@
@ flags:
@  FLAG 09: if SET suppress displaying result via ALPHA register
@
@ input:
@  ST X: magnetic field in Gauss
@
@ output:
@  ST X: energy difference in MHz
@
LBL "HLi6"
LSTO "_B"
FS? 09          @ skip ALPHA entries if FLAG 09 set
	GTO 01
CLA             @ add magnetic field information to ALPHA
"f("
AIP
├" G) = "
LBL 01          @ set up Hamiltonian and calculate energy difference
	XEQ A
	XEQ B
FS? 09          @ skip ALPHA entries if FLAG 09 set
	GTO 02
ARCL ST X       @ add frequency difference to ALPHA
├" MHz"
AVIEW
LBL 02
GTO 99          @ jump to end of program
LBL A           @ create Li6 ground state Hamiltonian
	1399624.5042    @ mu_B (Hz/G)
	RCL× "_B"
	2.002301        @ g_J
	RCL× "MJz"      @ J_z
	-0.000447654    @ g_I
	RCL× "MIz"      @ I_z
	+
	×
	152136840.7     @ a (Hz)
	RCL× "MJI"      @ J_I
	+
	STO "MZ"        @ H = a*J_I + B*mu_B*(g_J*J_z+g_I*I_z)
	RTN
LBL B           @ calculate energy difference between 1st and 2nd state in MHz
	RCL "REGS"
	LSTO "VREGS"    @ save current register values
	RCL "MZ"
	SF 01
	XEQ "TRED2"     @ transform H into tridiagonal shape
	SF 02
	XEQ "TQLI"      @ calculate eigenvalues from tridiagonal shape
	CF 02
	CF 01
	RCL "VREGS"
	STO "REGS"      @ restore register values
	RCL "VD"
	INDEX "VD"
	1
	2
	STOIJ
	R↓
	R↓
	RCLEL           @ energy of m_F = -1/2 state
	J-
	RCLEL           @ energy of m_F = +1/2 state
	-
	1ᴇ6
	÷               @ energy difference in MHz
	RTN
LBL 99          @ exit program
END