Add option to deposit current at arbitrary time (#1810)

* Introduce relative_time for deposition

* Deposit current at arbitrary time

* Update documentation

* Combine parameters in DepositCurrent

* Explicitly show the time at which the current is deposited

1 files changed, 17 insertions, 4 deletions

diff --git a/Source/Particles/WarpXParticleContainer.cpp b/Source/Particles/WarpXParticleContainer.cpp
index 304a0aa41..d838704a2 100644
--- a/Source/Particles/WarpXParticleContainer.cpp
+++ b/Source/Particles/WarpXParticleContainer.cpp
@@ -226,6 +226,11 @@ WarpXParticleContainer::AddNParticles (int /*lev*/,
  * \param lev         : Level of box that contains particles
  * \param depos_lev   : Level on which particles deposit (if buffers are used)
  * \param dt          : Time step for particle level
+ * \param relative_time: Time at which to deposit J, relative to the time of
+ *                       the current positions of the particles (expressed as
+ *                       a fraction of dt). When different than 0, the particle
+ *                       position will be temporarily modified to match the
+ *                       time of the deposition.
  */
 void
 WarpXParticleContainer::DepositCurrent(WarpXParIter& pti,
@@ -235,7 +240,7 @@ WarpXParticleContainer::DepositCurrent(WarpXParIter& pti,
                                        MultiFab* jx, MultiFab* jy, MultiFab* jz,
                                        const long offset, const long np_to_depose,
                                        int thread_num, int lev, int depos_lev,
-                                       Real dt)
+                                       Real dt, Real relative_time)
 {
     AMREX_ALWAYS_ASSERT_WITH_MESSAGE((depos_lev==(lev-1)) ||
                                      (depos_lev==(lev  )),
@@ -360,6 +365,14 @@ WarpXParticleContainer::DepositCurrent(WarpXParIter& pti,
         if ( (m_v_galilean[0]!=0) or (m_v_galilean[1]!=0) or (m_v_galilean[2]!=0)){
             amrex::Abort("The Esirkepov algorithm cannot be used with the Galilean algorithm.");
         }
+        if ( relative_time != -0.5_rt ) {
+            amrex::Abort("The Esirkepov deposition cannot be performed at another time then -0.5 dt.");
+        }
+    }
+    if (WarpX::current_deposition_algo == CurrentDepositionAlgo::Vay) {
+        if ( relative_time != -0.5_rt ) {
+          amrex::Abort("The Esirkepov deposition cannot be performed at another time then -0.5 dt.");
+        }
     }
 
     WARPX_PROFILE_VAR_START(blp_deposit);
@@ -417,21 +430,21 @@ WarpXParticleContainer::DepositCurrent(WarpXParIter& pti,
             doDepositionShapeN<1>(
                 GetPosition, wp.dataPtr() + offset, uxp.dataPtr() + offset,
                 uyp.dataPtr() + offset, uzp.dataPtr() + offset, ion_lev,
-                jx_fab, jy_fab, jz_fab, np_to_depose, dt, dx,
+                jx_fab, jy_fab, jz_fab, np_to_depose, dt*relative_time, dx,
                 xyzmin, lo, q, WarpX::n_rz_azimuthal_modes, cost,
                 WarpX::load_balance_costs_update_algo);
         } else if (WarpX::nox == 2){
             doDepositionShapeN<2>(
                 GetPosition, wp.dataPtr() + offset, uxp.dataPtr() + offset,
                 uyp.dataPtr() + offset, uzp.dataPtr() + offset, ion_lev,
-                jx_fab, jy_fab, jz_fab, np_to_depose, dt, dx,
+                jx_fab, jy_fab, jz_fab, np_to_depose, dt*relative_time, dx,
                 xyzmin, lo, q, WarpX::n_rz_azimuthal_modes, cost,
                 WarpX::load_balance_costs_update_algo);
         } else if (WarpX::nox == 3){
             doDepositionShapeN<3>(
                 GetPosition, wp.dataPtr() + offset, uxp.dataPtr() + offset,
                 uyp.dataPtr() + offset, uzp.dataPtr() + offset, ion_lev,
-                jx_fab, jy_fab, jz_fab, np_to_depose, dt, dx,
+                jx_fab, jy_fab, jz_fab, np_to_depose, dt*relative_time, dx,
                 xyzmin, lo, q, WarpX::n_rz_azimuthal_modes, cost,
                 WarpX::load_balance_costs_update_algo);
         }