Add-PSSnapin Microsoft.SharePoint.PowerShell -ErrorAction SilentlyContinue

    $webUrl = "HTTP://SITEURL"
    $listname = "LISTNAME"
    $fieldname = "FIELDNAME"
    $IsRequired = $False
    $FieldType = [Microsoft.SharePoint.SPFieldType]::Text

    $site = Get-SPSite $webUrl
    $Web = $site.OpenWeb()
    $list = $web.Lists.TryGetList($listname)
    $field = $list.Fields[$fieldname];

    if($field -eq $null)
    {
        $list.Fields.Add($fieldname,$FieldType,$IsRequired)
        $list.Update()
        Write-Host $fieldname "is created"
    }
    else
    {
        Write-Host $fieldname "is already exist"
    }